A ansi.sys | append | arp | assign | assoc | at | atmadm | attrib
B batch | backup | bootcfg | break
C cacls | call | cd | chcp | chdir | chdsk | chkntfs | choice | cipher | cls | cmd | color | command |comp | compact | control | convert | copy | ctty
D date | debug | defrag | del | delete | deltree | dir| disable | diskcomp | diskcopy | diskpart | |doskey | dosshell | driveparm
E echo | edit | edlin | emm386 | enable | endlocal | erase | exit | expand | extract
F fasthelp | fc | fdisk | find | findstr | fixboot | fixmbr | for| format | ftp | ftype
G goto | gpupdate | graftabl
H help | hostname
I if | ifhlp.sys | ipconfig
K keyb
L label | lh | listsvc | loadfix | loadhigh | lock | logoff | logon
M map | md | mem| mkdir | mode | more | move | msav | msbackup | msd | mscdex | mwbackup
N nbtstat | net | netsh | netstat | nlsfunc | nslookup
P path | pathping | pause | ping | popd | power | print | prompt | pushd
Q qbasic
R rd | reg | ren | rename | rmdir | route | runas
S scandisk | scanreg | set | setlocal | setver | sfc | share | shift | shutdown | smartdrv | sort | start | subst | switches | sys | systeminfo | ystemroot
T taskkill | telnet | time | title | tracert | tree | type
U undelete | unformat | unlock
V ver | verify | vol
Explain :-
About cd
CD (Change Directory) is a command used to switch directories in MS-DOS.
Syntax
CD [drive:][path]
CD[..]
About chdir
Chdir (Change Directory) is a command used to switch directories in MS-DOS.
Syntax
CHDIR [drive:][path]
CHDIR[..]
About copy
Allows the user to copy one or more files to an alternate location.
About date
The date command can be used to look at the current date of the computer as well as change the date to an alternate date.
About del
Del is a command used to delete files from the computer.
About dir
The dir command allows you to see the available files in the current and/or parent directories.
About dir
Erase is a command used to remove files from your computer's hard disk drive and or other writable media.
Syntax
Deletes one or more files.
DEL [drive:][path]filename
ERASE [drive:][path]filename
About exit
The exit command is used to withdrawal from the currently running application and/or the MS-DOS session.
About help
Help is used to access the information and help file from a MS-DOS prompt.
for example:
dir -help
or
dir /?
About hostname
Display the hostname of the machine the command is being run on. Additional information about the term hostname can be found on our hostname dictionary definition.
About logoff
The logoff command is an external command that allows a user to quickly logoff their computer from the command line or within a batch file.
About logon
The logon command is a recovery console command that lists the installations of Windows 2000 / Windows XP and requests the local administrator password for those installations.
About map
The map command is a recovery console command that displays the physical device name of a drive letter.
About md
Allows you to create your own directories in MS-DOS.
Syntax
Creates a directory.
MKDIR [drive:]path
MD [drive:]path
About ping
Helps in determining TCP/IP Networks IP address as well as determine issues with the network and assists in resolving them.
See our dictionary ping definition for additional information.
About rd / rmdir
Removes empty directories in MS-DOS. To delete directories with files or directories
About ren and rename
Used to rename files and directories from the original name to a new name.
Syntax
Renames a file/directory or files/directories.
RENAME [drive:][path][directoryname1 | filename1] [directoryname2 | filename2]
REN [drive:][path][directoryname1 | filename1] [directoryname2 | filename2]
About start
Enables a user to start a separate window in Windows from the MS-DOS prompt.
About tree
Allows the user to view a listing of files and folders in an easy to read listing.
About time
Allows the user to view and edit the computer's time.
About lock / unlick
Lock allows a user to lock a drive, enabling direct disk access for an application.
Unlock allows a users to unlock a drive, disabling direct disk access for an application
Syntax
LOCK [drive:]
drive:
Specifies the drive that needs to be locked.
UNLOCK [drive:]
drive:
Specifies the drive that needs to be unlocked.
About ver
Displays the version of MS-DOS or if running
About verify
Enables or disables the feature to determine if files have been written properly.
About vol
Displays the volume information about the designated drive.
About comp
A simple compare that compares two or more files.
Syntax
Compares the contents of two files or sets of files.
COMP [data1] [data2]
About xcopy
Xcopy is a powerful version of the copy command with additional features; has the capability of moving files, directories, and even whole drives from one location to another.
About path
Path is used to specify the location where MS-DOS looks when using a command.
Saturday, August 16, 2008
Tuesday, August 5, 2008
What is Spam(In yahoo mail)?
Spam is any message or posting, regardless of its content, that is sent to multiple recipients who have not specifically requested the mail. It can also be multiple postings of the same message to Newsgroups or list servers that are not related to the topic of the message. Other common terms on the Internet are UCE (Unsolicited Commercial Email) and UBE (Unsolicited Bulk Email) which are the same as what is typically called spam.
The individuals who send spam are typically people who have purchased or harvested a list of email addresses. And they send messages from numerous different addresses to all areas of the Web. (*We do not give away or sell the information you provide to us. This includes, but is not limited to, anyone who is interested in sending unsolicited mail to your account.)
All mail originating from Yahoo! has an originating IP address embedded in the full address headers which helps to identify the sender of the email and track the individual to his or her service provider. Individuals who use a Yahoo! address in their spam are forging mail headers if the originating IP line is absent in the spam you receive.
OR
Spam is any message that's sent to multiple recipients who haven't specifically requested the message. In other words, spam is crap.
Spammers typically purchase or harvest a list of email addresses. They send messages from numerous different addresses to all areas of the Web. These messages tend to be "forged," to hide who actually sent them.
if you marked a message as spam by mistake. What should you do?
Don't worry! This is easy to fix. When you clicked "Spam," the message went into your Spam folder.
1. Open the Spam folder by clicking it in the folder list on the left of the page
2. Click the message that you marked spam by mistake.
3. Click the "Not Spam" button along the top of the window.
How long do messages stay in my Spam Folder? Can I control this?
Yes. Here’s how you do it:
* Click Options in the upper-right corner of your Mail page.
* Click Spam from the list on the left.
* In the “SpamGuard” section, after the line “Empty Spam folder”, you can specify how often you’d like us to empty your Spam folder by selecting from the pull-down menu. We do it automatically once a month, but you can select two weeks, one week…or immediately!
* Above your spam options, click Save Changes.
The individuals who send spam are typically people who have purchased or harvested a list of email addresses. And they send messages from numerous different addresses to all areas of the Web. (*We do not give away or sell the information you provide to us. This includes, but is not limited to, anyone who is interested in sending unsolicited mail to your account.)
All mail originating from Yahoo! has an originating IP address embedded in the full address headers which helps to identify the sender of the email and track the individual to his or her service provider. Individuals who use a Yahoo! address in their spam are forging mail headers if the originating IP line is absent in the spam you receive.
OR
Spam is any message that's sent to multiple recipients who haven't specifically requested the message. In other words, spam is crap.
Spammers typically purchase or harvest a list of email addresses. They send messages from numerous different addresses to all areas of the Web. These messages tend to be "forged," to hide who actually sent them.
if you marked a message as spam by mistake. What should you do?
Don't worry! This is easy to fix. When you clicked "Spam," the message went into your Spam folder.
1. Open the Spam folder by clicking it in the folder list on the left of the page
2. Click the message that you marked spam by mistake.
3. Click the "Not Spam" button along the top of the window.
How long do messages stay in my Spam Folder? Can I control this?
Yes. Here’s how you do it:
* Click Options in the upper-right corner of your Mail page.
* Click Spam from the list on the left.
* In the “SpamGuard” section, after the line “Empty Spam folder”, you can specify how often you’d like us to empty your Spam folder by selecting from the pull-down menu. We do it automatically once a month, but you can select two weeks, one week…or immediately!
* Above your spam options, click Save Changes.
Monday, August 4, 2008
Connecting Modem in LINUX(ubuntu)
Firstly connect the modem with your computer
Then start the linux OP. System
Go throw step vice step :-
> Open the terminal( Application > accessories> teminal)
> in the terminal, type command
sudo pppoeconf
>Confime that your Ethernet card is detceted
> Then enter username
> Enter password
>If you have pppoe connection is configured ,you will be asked if it may be modifed
> Popular options: you may asked if you want the "noauth " and "defaultroute" and to remove nodetach and choose yes
>Use peer DNS - Choose yes
> limited MMS problem - choose yes
>When ure asked if you want to connet to start up, you will probbaly want to say yes
>Finaly you are asked if you want to establish the connection immediately
once you have finished these steps, your connection should be working
Then start the linux OP. System
Go throw step vice step :-
> Open the terminal( Application > accessories> teminal)
> in the terminal, type command
sudo pppoeconf
>Confime that your Ethernet card is detceted
> Then enter username
> Enter password
>If you have pppoe connection is configured ,you will be asked if it may be modifed
> Popular options: you may asked if you want the "noauth " and "defaultroute" and to remove nodetach and choose yes
>Use peer DNS - Choose yes
> limited MMS problem - choose yes
>When ure asked if you want to connet to start up, you will probbaly want to say yes
>Finaly you are asked if you want to establish the connection immediately
once you have finished these steps, your connection should be working
Saturday, August 2, 2008
How to Flag a Message for Follow-Up in Yahoo! Mail
It's best to read every email only once and reply to it, file it or trash it immediately. It's best, but it is not always possible.
If you can't deal with a new message in Yahoo! Mail immediately, you can highlight it so you don't forget to return to it later.
While marking to-do messages unread works, a dedicated, more elegant and generally better way to flag emails for follow-up exists. Message flags are particularly useful in Yahoo! Mail if you use them with Message Views.
Flag a Message for Follow-Up in Yahoo! Mail
To flag an email in Yahoo! Mail:
* Highlight the message in the mailbox or open it in its own tab.
* Press L (think flag).
o Alternatively, click in the flag column to toggle a message's flag status.
To remove the flag from a message, press Shift-L.
Flag a Message for Follow-Up in Yahoo! Mail Classic
To flag a message for follow-up in Yahoo! Mail Classic:
* Make sure the checkbox next to the message you want to flag is selected in a Yahoo! Mail folder.
o You can also select and mark multiple messages at once.
* Click on the Mark button.
* Select Flag for Follow-up from the menu.
You can also flag a message by opening it and clicking the flag in the message's top left corner.
To clear a message flag in Yahoo! Mail, check its box in the folder view and select Clear Flag from the Mark button's menu.
If you can't deal with a new message in Yahoo! Mail immediately, you can highlight it so you don't forget to return to it later.
While marking to-do messages unread works, a dedicated, more elegant and generally better way to flag emails for follow-up exists. Message flags are particularly useful in Yahoo! Mail if you use them with Message Views.
Flag a Message for Follow-Up in Yahoo! Mail
To flag an email in Yahoo! Mail:
* Highlight the message in the mailbox or open it in its own tab.
* Press L (think flag).
o Alternatively, click in the flag column to toggle a message's flag status.
To remove the flag from a message, press Shift-L.
Flag a Message for Follow-Up in Yahoo! Mail Classic
To flag a message for follow-up in Yahoo! Mail Classic:
* Make sure the checkbox next to the message you want to flag is selected in a Yahoo! Mail folder.
o You can also select and mark multiple messages at once.
* Click on the Mark button.
* Select Flag for Follow-up from the menu.
You can also flag a message by opening it and clicking the flag in the message's top left corner.
To clear a message flag in Yahoo! Mail, check its box in the folder view and select Clear Flag from the Mark button's menu.
Unlimited Storage! in yahoo mail
How does unlimited storage work?
It’s pretty straightforward—users that follow normal email practices and comply with our anti-abuse limits can consume an unlimited amount of free email storage. This will apply to both new and existing users.
Wait – what? Wow!
How can Yahoo! afford to give away unlimited email storage?
By hiring outstanding engineers, of course! Ours have been hard at work developing an incredibly efficient backend storage system. Protected by responsive anti-abuse controls, this updated storage system gives you the option to never delete another email! Unless, of course, you want to.
How will you prevent abuse?
Responsive anti-abuse controls enable us to effectively identify anyone who’s taking advantage of Yahoo!’s email service. We want to ensure that everyone benefits from unlimited storage!
What exactly does unlimited storage mean?
The purpose of unlimited storage isn’t to provide an online storage warehouse. Usage that suggests this approach gets flagged by Yahoo! Mail’s anti-abuse controls.
Unlimited storage gives normal email account users like yourself an opportunity to not have to worry about hitting a storage limit. Basically, the idea is that now you can save your correspondence and memories and never worry about deleting older messages to make room for more.
It’s pretty straightforward—users that follow normal email practices and comply with our anti-abuse limits can consume an unlimited amount of free email storage. This will apply to both new and existing users.
Wait – what? Wow!
How can Yahoo! afford to give away unlimited email storage?
By hiring outstanding engineers, of course! Ours have been hard at work developing an incredibly efficient backend storage system. Protected by responsive anti-abuse controls, this updated storage system gives you the option to never delete another email! Unless, of course, you want to.
How will you prevent abuse?
Responsive anti-abuse controls enable us to effectively identify anyone who’s taking advantage of Yahoo!’s email service. We want to ensure that everyone benefits from unlimited storage!
What exactly does unlimited storage mean?
The purpose of unlimited storage isn’t to provide an online storage warehouse. Usage that suggests this approach gets flagged by Yahoo! Mail’s anti-abuse controls.
Unlimited storage gives normal email account users like yourself an opportunity to not have to worry about hitting a storage limit. Basically, the idea is that now you can save your correspondence and memories and never worry about deleting older messages to make room for more.
Filesystem Hierarchy Standard (FHS) of Linux
The Filesystem Hierarchy Standard (FHS) defines the main directories and their contents in most Linux-based computer operating systems. It is a formalization and extension of common UNIX practices.
In the FHS all files and directories appear under the root directory "/", even if they are stored on different physical devices. Note however that some of these directories may or may not be present on a Unix system depending on whether certain subsystems, such as the X Window System, are installed.
The majority of these directories exist in all UNIX operating systems and are generally used in much the same way; however, the descriptions here are those used specifically for the FHS, and are not considered authoritative for platforms other than Linux.
In the FHS all files and directories appear under the root directory "/", even if they are stored on different physical devices. Note however that some of these directories may or may not be present on a Unix system depending on whether certain subsystems, such as the X Window System, are installed.
The majority of these directories exist in all UNIX operating systems and are generally used in much the same way; however, the descriptions here are those used specifically for the FHS, and are not considered authoritative for platforms other than Linux.
General Public License (GPL)
The GNU General Public License (GNU GPL or simply GPL) is a widely used free software license, originally written by Richard Stallman for the GNU project. The GPL is the most popular and well-known example of the type of strong copyleft license that requires derived works to be available under the same copyleft. Under this philosophy, the GPL is said to grant the recipients of a computer program the rights of the free software definition and uses copyleft to ensure the freedoms are preserved, even when the work is changed or added to. This is in distinction to permissive free software licenses, of which the BSD licenses are the standard examples.
The GNU Lesser General Public License (LGPL) is a modified, more permissive, version of the GPL, originally intended for some software libraries. There is also a GNU Free Documentation License, which was originally intended for use with documentation for GNU software, but has also been adopted for other uses, such as the Wikipedia project.
Terms and conditions
The terms and conditions of the GPL are available to anybody receiving a copy of the work that has a GPL applied to it ("the licensee"). Any licensee who adheres to the terms and conditions is given permission to modify the work, as well as to copy and redistribute the work or any derivative version. The licensee is allowed to charge a fee for this service, or do this free of charge. This latter point distinguishes the GPL from software licenses that prohibit commercial redistribution. The FSF argues that free software should not place restrictions on commercial use,[21] and the GPL explicitly states that GPL works may be sold at any price.
The GPL additionally states that a distributor may not impose "further restrictions on the rights granted by the GPL". This forbids activities such as distributing of the software under a non-disclosure agreement or contract. Distributors under the GPL also grant a license for any of their patents practiced by the software, to practice those patents in GPL software.
Section three of the license requires that programs distributed as pre-compiled binaries are accompanied by a copy of the source code, a written offer to distribute the source code via the same mechanism as the pre-compiled binary or the written offer to obtain the source code that you got when you received the pre-compiled binary under the GPL.
The GNU Lesser General Public License (LGPL) is a modified, more permissive, version of the GPL, originally intended for some software libraries. There is also a GNU Free Documentation License, which was originally intended for use with documentation for GNU software, but has also been adopted for other uses, such as the Wikipedia project.
Terms and conditions
The terms and conditions of the GPL are available to anybody receiving a copy of the work that has a GPL applied to it ("the licensee"). Any licensee who adheres to the terms and conditions is given permission to modify the work, as well as to copy and redistribute the work or any derivative version. The licensee is allowed to charge a fee for this service, or do this free of charge. This latter point distinguishes the GPL from software licenses that prohibit commercial redistribution. The FSF argues that free software should not place restrictions on commercial use,[21] and the GPL explicitly states that GPL works may be sold at any price.
The GPL additionally states that a distributor may not impose "further restrictions on the rights granted by the GPL". This forbids activities such as distributing of the software under a non-disclosure agreement or contract. Distributors under the GPL also grant a license for any of their patents practiced by the software, to practice those patents in GPL software.
Section three of the license requires that programs distributed as pre-compiled binaries are accompanied by a copy of the source code, a written offer to distribute the source code via the same mechanism as the pre-compiled binary or the written offer to obtain the source code that you got when you received the pre-compiled binary under the GPL.
BELIEVE IN GOD
What is the meaning of believe?
Simple meaning of believe is faith in someone else.
The important thing about belief is that thing it is a necessary step toward knowing. Knowing is proving the belief through your own experiences, and trying it from enough different angles to see how it holds up.
WHAT IS GOD?
No body can see.
No body can hear.
No body can imagine the GOD.
No body can suppose the GOD.
No body can Explain what is GOD?
But some person can feel the GOD.
GOD is never present in a single place.
GOD is everywhere.
God is owner of all things
Every thing exist for a purpose and reason
God is the central fact of the universe
The truth about GOD has been made known to everyone
Millions of stars placed in the skies , by one God.
Many the ways all of us pray , to one God.
In a World Three Types Of Peoples
Atheist
Someone who doesn’t believe in God
Agnostic
Someone who is unsure about God
Theist
Someone who believes in God
Atheist Person
A person cannot believe in GOD in present time.
He can remember GOD when he in struggle or in last time of his life i.e. when death is near to him.
Then they said a words “O' GOD help me”(or Hai rabba)
Agnostic person
The persons whose ideas are in between in atheist and theist are confused about the GOD in whole life .
But,in the end of their life, they realize and feel that GOD is everywhere and everybody can feel if they make their believe in GOD .
Theist Person
The persons remember the GOD every time in our whole life and believe in GOD.
They feel themselves little bit close to the GOD. They make their mind stable and have no excitement about anything.
And they have their control on five vices or five demons i.e. (ego , greed , anger , attachment , lust)
At last I thank GOD for preserving my life, for supplying shelter, food and all my needs.
Thank god for the loneliness, for work, for difficulties and problems, for uncertainties and tears because all these brought me closer to GOD.
THANKS TO GOD
Simple meaning of believe is faith in someone else.
The important thing about belief is that thing it is a necessary step toward knowing. Knowing is proving the belief through your own experiences, and trying it from enough different angles to see how it holds up.
WHAT IS GOD?
No body can see.
No body can hear.
No body can imagine the GOD.
No body can suppose the GOD.
No body can Explain what is GOD?
But some person can feel the GOD.
GOD is never present in a single place.
GOD is everywhere.
God is owner of all things
Every thing exist for a purpose and reason
God is the central fact of the universe
The truth about GOD has been made known to everyone
Millions of stars placed in the skies , by one God.
Many the ways all of us pray , to one God.
In a World Three Types Of Peoples
Atheist
Someone who doesn’t believe in God
Agnostic
Someone who is unsure about God
Theist
Someone who believes in God
Atheist Person
A person cannot believe in GOD in present time.
He can remember GOD when he in struggle or in last time of his life i.e. when death is near to him.
Then they said a words “O' GOD help me”(or Hai rabba)
Agnostic person
The persons whose ideas are in between in atheist and theist are confused about the GOD in whole life .
But,in the end of their life, they realize and feel that GOD is everywhere and everybody can feel if they make their believe in GOD .
Theist Person
The persons remember the GOD every time in our whole life and believe in GOD.
They feel themselves little bit close to the GOD. They make their mind stable and have no excitement about anything.
And they have their control on five vices or five demons i.e. (ego , greed , anger , attachment , lust)
At last I thank GOD for preserving my life, for supplying shelter, food and all my needs.
Thank god for the loneliness, for work, for difficulties and problems, for uncertainties and tears because all these brought me closer to GOD.
THANKS TO GOD
Linux Commands used in Terminal
ls -list the files and directories.
cd -change the diretory
cd/ - the folder comes to the root
cal - show calendar
mkdir directory name - create directory
rmdir directory name - remove directory
cat > file name - create file
ctrl +z - stop and save data
cat file name - show the data file
cat >> file name - append data in file
pwd - present / print working directory
who - display information about all user on system
whoami -Tells the name of user currently logged in
man - Provides manual data about any file or command
wc - display the no. of lines words , and characters in that files and also tell the name of file
banner - It displays the massage in large size
ls- l file name - prints authorization for each file
chmod - chamnge the permisson
date - display the date
grep - searches a particular content
grep -c - count tne no. of tatal lines
grep -n - display line no. in which the content is present
adduser - create user
hostname - print the name of local host
last - show listing of user logged in on computer
free - check memory status
uname - print system information
man - for help
date -show date
ls -l - list of file and directory
sudo init 0 -shutdown computer
sudo init 6 - restart computer
clear - clear terminal screen
comm - compared two files line by line
cp - copy one or more files to another location
df - display free disk space
diff - display the diffrence between two file
dir - briefiy list directory contents
du - estimate file space
expand - convert tabs into space
kill - stop a process from running
logout - exit a login shell
more, less - display output on screen at a time
paste - merge lines of files
ping - test network connection
pr - prepare files for printing
return - exit shell function
rm - remove files
sleep - delay for specfied time
tail - output of last part of file
users - list users currrently logged in
usermod - modify user account
units - convert unit from one scale to another
free -m or $free -t -m - to find the memory space in the system using command line
cd -change the diretory
cd/ - the folder comes to the root
cal - show calendar
mkdir directory name - create directory
rmdir directory name - remove directory
cat > file name - create file
ctrl +z - stop and save data
cat file name - show the data file
cat >> file name - append data in file
pwd - present / print working directory
who - display information about all user on system
whoami -Tells the name of user currently logged in
man - Provides manual data about any file or command
wc - display the no. of lines words , and characters in that files and also tell the name of file
banner - It displays the massage in large size
ls- l file name - prints authorization for each file
chmod - chamnge the permisson
date - display the date
grep - searches a particular content
grep -c - count tne no. of tatal lines
grep -n - display line no. in which the content is present
adduser - create user
hostname - print the name of local host
last - show listing of user logged in on computer
free - check memory status
uname - print system information
man - for help
date -show date
ls -l - list of file and directory
sudo init 0 -shutdown computer
sudo init 6 - restart computer
clear - clear terminal screen
comm - compared two files line by line
cp - copy one or more files to another location
df - display free disk space
diff - display the diffrence between two file
dir - briefiy list directory contents
du - estimate file space
expand - convert tabs into space
kill - stop a process from running
logout - exit a login shell
more, less - display output on screen at a time
paste - merge lines of files
ping - test network connection
pr - prepare files for printing
return - exit shell function
rm - remove files
sleep - delay for specfied time
tail - output of last part of file
users - list users currrently logged in
usermod - modify user account
units - convert unit from one scale to another
free -m or $free -t -m - to find the memory space in the system using command line
ssh -p 756 aaa@....
scp -P 756 filename ab@..... :filename
Database de-limiter exchange or replace character
To convert a comma delimited database file with a file which is tab delimited:
$tr ',' '\t' < file > newfile
Database de-limiter exchange or replace character
To convert a comma delimited database file with a file which is tab delimited:
$tr ',' '\t' < file > newfile
To see every process on the Unix like system use the following standard syntax:
ps -e
ps -ef
ps -eF
ps -ely
ps axu
INTERNET
INTRODUCTION
The Internet is a seamless network of communication lines connecting hardware and software across the world using communication protocol to exchange information . The Internet links are the computer networks all over the world so that users can share resources and communicate with each other . Internet is the tool that will take you beyond telephones , faxes , and isolated computers to a burgeoning networked information frontier .The Internet supplements the traditional tools you use to gather information , Data Graphics, News and correspond with other people.
What is the Internet?
The Internet links are computer networks all over the world so that users can share resources and communicate with each other. The Internet is what we call a metanetwork, that is, a network of networks that spans the globe. It's impossible to give an exact count of the number of networks or users that comprise the Internet, but it is easily in the thousands and millions respectively .The Internet is also what we call a distributed system; there is no central archives. Technically, no one runs the Internet. Rather, the Internet is made up of
thousands of smaller networks.
History & Development of Internet
Internet was originally conceived by the Department of Defense as a way to protect government communications systems in the event of a military strike. The original network, dubbed ARPANet (Advanced Research Projects Agency ) evolved into a communications channel among contractors, military personnel, and university researchers. The network employed a set of standard protocols to create an effective way for these people to communicate and share data with each other. By the
late 1980's,thousands of cooperating networks were participating in the Internet.In1991' the U.S. high performance computing act established the NREN (national research & education network).Internet has been improved through the developments of such services as gopher and the world wild web .
INTERNET TOOLS
Browser/server security information- for reading all header and Javascript information available from web page or your browser
Web browser – Mozilla firefox, Netscape ,internet explorer,etc
Web content analysis -complex analysis of a web page content. Highly recommended for web developers.
Web Traffic analysis - Tons of information about site popularity on the Internet (historical traffic, ranking, page views and more). Highly recommended for web marketing!
Geographical IP look up- it shows ability to find geographical location based on IP address. It displays interactive map with address information.
FEATURES
Key Features
Geographic Distribution
Robust Architecture
Near Light Speed
Universal Access
Internet Growth Rates
The Digital Advantage
Freedom Of Speech
Key Web Features
Ease Of Use
Universal Access
Search Capabilities
Key features of Email
Email is push technology
Email waits for you
Email is one-to-many
Email is almost free
Key Usenet Newsgroups Features
Group Communications
Common Space
APPLICATION OF INTERNET
WWW( world wide web)-The World Wide Web (also referred to as WWW or W3) is the fastest growing area of the Internet. Documents on the WWW include text, images, video, and audio for a very exciting presentation. People who create WWW documents often include a photograph of themselves along with detailed professional information and personal interests.
E-Mail (electronic mail) -E-mail is an asynchronous form of communication, meaning that the person whom you want to read your message doesn't have to be available at the precise moment you send your message. This is a great convenience for both you and the recipient.
FTP(File Transfer Protocol) -To do FTP, a user invokes one of two commands: get the command for transferring a file from another server to your own computer.
put the command for moving a file from your computer to another one.
Resources available
Freeware
Public domain
Shareware
SMTP(Simple-Mail Transfer Protocol)
Network news
Search Engines
ADVANTAGES
CommunicatiSn
Information
Entertainment
Services
E-Commerce
Business
Web browsers
Any kind of information you can search on Internet
DISADVANTAGES OF INTERNET
Excessive use causes health hazards .
Cyber crime.
Fraudulent(deceitful) information.
Provides virtual society,but human being remains isolated in his small rooms.
Wastage of time due to chat like services.
Viruses, worm,etc , may damage data and information.
Kernel is opreating system
In computer science, the kernel is the central component of most computer operating systems (OS). Its responsibilities include managing the system's resources (the communication between hardware and software components).
[1] As a basic component of an operating system, a kernel provides the lowest-level abstraction layer for the resources (especially memory, processors and I/O devices) that application software must control to perform its function. It typically makes these facilities available to application processes through inter-process communication mechanisms and system calls.
These tasks are done differently by different kernels, depending on their design and implementation. While monolithic kernels will try to achieve these goals by executing all the code in the same address space to increase the performance of the system, microkernels run most of their services in user space, aiming to improve maintainability and modularity of the codebase
[1] As a basic component of an operating system, a kernel provides the lowest-level abstraction layer for the resources (especially memory, processors and I/O devices) that application software must control to perform its function. It typically makes these facilities available to application processes through inter-process communication mechanisms and system calls.
These tasks are done differently by different kernels, depending on their design and implementation. While monolithic kernels will try to achieve these goals by executing all the code in the same address space to increase the performance of the system, microkernels run most of their services in user space, aiming to improve maintainability and modularity of the codebase
Assembley langauge
Introduction :-
An assembly language is a low-level language for programming computers. Assembly language is the most basic programming language available for any processor. Assembly language is also the most powerful computer programming language available, and it gives programmers the insight required to write effective code in high-level languages. Learning assembly language is well worth the time and effort of every serious programmer. With assembly language , a programmer works only with operations implemented directly on physical CPU. Assembly language lacks high-level conveniences such as variables and functions, and it is not portable between various families of processors.
Assembly language is not a single language, but rather a group of languages. Each processor family (and sometimes individual processors within a processor family) has its own assembly language.
Why learn assembly language?
The first reason to work with assembler is that it provides the opportunity of knowing more the operation of your PC, which allows the development of software in a more consistent manner.
The second reason is the total control of the PC which you can have with the use of the assembler.
Another reason is that the assembly programs are quicker, smaller, and have larger capacities than ones created with other languages.
Assembly language allows an ideal optimization in programs, be it on their size or on their execution.
Comparison of Assembly and High level language :-
The assembly language contains more instruction than High level language. In the assembly language program written on one computer can't be used on any other computer. But In high level language the program written on one computer can be used on other computer . In Assembly language program runs faster to produce the desired result as compared to high level language. The computation in high level language program is less than assembly language.
Syntax
Assembly language has two main syntax branches: AT&T syntax and Intel syntax, originally used for the documentation of the x86 platform. The Intel syntax is dominant in the Windows world. In the Unix/Linux world, both are in used .Here is a summarized list of the main differences between Intel syntax and AT&T syntax:
In AT&T syntax, the source comes before the destination, in the opposite style from Intel syntax
In AT&T syntax, the opcodes are suffixed with a letter indicating the size of the operands (e.g. "l" for dword, "w" for word, and "b" for byte)
In AT&T syntax, immediate values must be prefixed with a "$", and registers must be prefixed with a "%".
In AT&T syntax, effective addresses use the general syntax DISP(BASE,INDEX,SCALE), whereas in Intel syntax, effective addresses use variables, and need to be in square brackets; additionally, size keywords like 'byte', 'word' or 'dword' have to be used.
Basic Concepts of Assembly Language
Assembler structure:- In assembly language code lines have two parts, the first one is the name of the instruction which is to be executed, and the second one are the parameters of the command. For example: add ah bh
Here "add" is the command to be executed, in this case an addition, and "ah" as well as "bh" are the parameters.
Information Units :- In order for the PC to process information, it is necessary that this information be in special cells called registers. The registers are groups of 8 or 16 flip-flops. A group of 16 bits is known as word; a word can be divided in groups of 8 bits called bytes, and the groups of 4 bits are called nibbles.
Numeric systems:- The numeric system we use daily is the decimal system, but this system is not convenient for machines since the information is handled codified in the shape of on or off bits.
Converting binary numbers to decimals :-
When working with assembly language we come on the necessity of converting numbers from the binary system, which is used by computers and the decimal system used by people. The binary system is based on only two conditions or states, be it on(1) or off(0), thus its base is two.
For the conversion we can use the positional value formula: For example Binary: 1 1 0 0 1
Decimal: 1*2^0 + 1*2^1 + 0*2^2 + 0*2^3 + 1*2^4 = 1 + 2 + 0 + 0 + 16 = 19
Converting decimal numbers to binary :-
Let us take for example the decimal number of 43.
43/2=21 and its residue is 1
21/2=10 and its residue is 1
10/2=5 and its residue is 0
5/2=2 and its residue is 1
2/2=1 and its residue is 0
1/2=0 and its residue is 1
Building the number from the bottom , we get that the binary result is
101011
Hexadecimal system
On the hexadecimal base we have 16 digits which go from 0 to 9 and from the letter A to the F, these letters represent the numbers from 10 to 15. Thus we count 0,1,2,3,4,5,6,7,8,9,A,B,C,D,E, and F.
The conversion between binary and hexadecimal numbers is easy. The first thing done to do a conversion of a binary number to a hexadecimal is to divide it in groups of 4 bits, beginning from the right to the left. In case the last group, the one most to the left, is under 4 bits, the missing places are filled with zeros.
Use of assembly language:-
Historical perspective
Historically, a large number of programs have been written entirely in assembly language. Operating systems were almost exclusively written in assembly language until the widespread acceptance of C in the 1970s and early 1980s. Many commercial applications were written in assembly language as well, including a large amount of the IBM mainframe software written by large corporations. Most early microcomputers relied on hand-coded assembly language, including most operating systems and large applications. In a more commercial context, the biggest reasons for using assembly language were size (and hence speed), and reliability.
Typical Applications
Hard-coded assembly language is typically used in a system's boot ROM . This low-level code is used , among other things , to initialize and test the system hardware prior to booting the OS, and is stored in ROM . Assembly language is also valuable in reverse engineering , since many programs are distributed only in machine code form , and machine code is usually easy to translate into assembly language and carefully examine in this form, but very difficult to translate into a higher-level language. Tools such as the interaction Disassembler make extensive use of disassembly for such a purpose.
An assembly language is a low-level language for programming computers. Assembly language is the most basic programming language available for any processor. Assembly language is also the most powerful computer programming language available, and it gives programmers the insight required to write effective code in high-level languages. Learning assembly language is well worth the time and effort of every serious programmer. With assembly language , a programmer works only with operations implemented directly on physical CPU. Assembly language lacks high-level conveniences such as variables and functions, and it is not portable between various families of processors.
Assembly language is not a single language, but rather a group of languages. Each processor family (and sometimes individual processors within a processor family) has its own assembly language.
Why learn assembly language?
The first reason to work with assembler is that it provides the opportunity of knowing more the operation of your PC, which allows the development of software in a more consistent manner.
The second reason is the total control of the PC which you can have with the use of the assembler.
Another reason is that the assembly programs are quicker, smaller, and have larger capacities than ones created with other languages.
Assembly language allows an ideal optimization in programs, be it on their size or on their execution.
Comparison of Assembly and High level language :-
The assembly language contains more instruction than High level language. In the assembly language program written on one computer can't be used on any other computer. But In high level language the program written on one computer can be used on other computer . In Assembly language program runs faster to produce the desired result as compared to high level language. The computation in high level language program is less than assembly language.
Syntax
Assembly language has two main syntax branches: AT&T syntax and Intel syntax, originally used for the documentation of the x86 platform. The Intel syntax is dominant in the Windows world. In the Unix/Linux world, both are in used .Here is a summarized list of the main differences between Intel syntax and AT&T syntax:
In AT&T syntax, the source comes before the destination, in the opposite style from Intel syntax
In AT&T syntax, the opcodes are suffixed with a letter indicating the size of the operands (e.g. "l" for dword, "w" for word, and "b" for byte)
In AT&T syntax, immediate values must be prefixed with a "$", and registers must be prefixed with a "%".
In AT&T syntax, effective addresses use the general syntax DISP(BASE,INDEX,SCALE), whereas in Intel syntax, effective addresses use variables, and need to be in square brackets; additionally, size keywords like 'byte', 'word' or 'dword' have to be used.
Basic Concepts of Assembly Language
Assembler structure:- In assembly language code lines have two parts, the first one is the name of the instruction which is to be executed, and the second one are the parameters of the command. For example: add ah bh
Here "add" is the command to be executed, in this case an addition, and "ah" as well as "bh" are the parameters.
Information Units :- In order for the PC to process information, it is necessary that this information be in special cells called registers. The registers are groups of 8 or 16 flip-flops. A group of 16 bits is known as word; a word can be divided in groups of 8 bits called bytes, and the groups of 4 bits are called nibbles.
Numeric systems:- The numeric system we use daily is the decimal system, but this system is not convenient for machines since the information is handled codified in the shape of on or off bits.
Converting binary numbers to decimals :-
When working with assembly language we come on the necessity of converting numbers from the binary system, which is used by computers and the decimal system used by people. The binary system is based on only two conditions or states, be it on(1) or off(0), thus its base is two.
For the conversion we can use the positional value formula: For example Binary: 1 1 0 0 1
Decimal: 1*2^0 + 1*2^1 + 0*2^2 + 0*2^3 + 1*2^4 = 1 + 2 + 0 + 0 + 16 = 19
Converting decimal numbers to binary :-
Let us take for example the decimal number of 43.
43/2=21 and its residue is 1
21/2=10 and its residue is 1
10/2=5 and its residue is 0
5/2=2 and its residue is 1
2/2=1 and its residue is 0
1/2=0 and its residue is 1
Building the number from the bottom , we get that the binary result is
101011
Hexadecimal system
On the hexadecimal base we have 16 digits which go from 0 to 9 and from the letter A to the F, these letters represent the numbers from 10 to 15. Thus we count 0,1,2,3,4,5,6,7,8,9,A,B,C,D,E, and F.
The conversion between binary and hexadecimal numbers is easy. The first thing done to do a conversion of a binary number to a hexadecimal is to divide it in groups of 4 bits, beginning from the right to the left. In case the last group, the one most to the left, is under 4 bits, the missing places are filled with zeros.
Use of assembly language:-
Historical perspective
Historically, a large number of programs have been written entirely in assembly language. Operating systems were almost exclusively written in assembly language until the widespread acceptance of C in the 1970s and early 1980s. Many commercial applications were written in assembly language as well, including a large amount of the IBM mainframe software written by large corporations. Most early microcomputers relied on hand-coded assembly language, including most operating systems and large applications. In a more commercial context, the biggest reasons for using assembly language were size (and hence speed), and reliability.
Typical Applications
Hard-coded assembly language is typically used in a system's boot ROM . This low-level code is used , among other things , to initialize and test the system hardware prior to booting the OS, and is stored in ROM . Assembly language is also valuable in reverse engineering , since many programs are distributed only in machine code form , and machine code is usually easy to translate into assembly language and carefully examine in this form, but very difficult to translate into a higher-level language. Tools such as the interaction Disassembler make extensive use of disassembly for such a purpose.
Pointer
POINTER :- are the variables which are used for holding address of variables or that are memory location that hold variables address
*p is pointer variables
**p is pointer to pointer variables
Use of pointer in C++
1.A pointer enables the variable used outside the function or in another sub program
2.Increases execution speed in C++ programming
3.It reduces Strength and Complexity
4.Pointers are more efficient in handling data table i.e 2 D Arrays
5.use of the pointer to the character away or code to the string saves storage space in memory
6.Pointer gives accurate results
7.we can make c++ programming easier by the use of pointer
8. pointers have direct link with structure and union by linking with structure we can increase execution speed of the programs
9.pointer saves memory space and this can be done by using dynamic memory allocation
10. pointers are very useful to handle files,data structure and manipulation.
11.pointers are used for addressing by using the hashing technique
*p is pointer variables
**p is pointer to pointer variables
Use of pointer in C++
1.A pointer enables the variable used outside the function or in another sub program
2.Increases execution speed in C++ programming
3.It reduces Strength and Complexity
4.Pointers are more efficient in handling data table i.e 2 D Arrays
5.use of the pointer to the character away or code to the string saves storage space in memory
6.Pointer gives accurate results
7.we can make c++ programming easier by the use of pointer
8. pointers have direct link with structure and union by linking with structure we can increase execution speed of the programs
9.pointer saves memory space and this can be done by using dynamic memory allocation
10. pointers are very useful to handle files,data structure and manipulation.
11.pointers are used for addressing by using the hashing technique
C++
Control Statements :- are the way of the program to control what pieces of program to be executed at same time the syntax of control statement are very similar to the regular english thre are two types are control statment :
^branching statement and
^loop
and the if, else, while ,do while,for, exit(), return,switch,go to,continue etc are control statements
Manibulators :- endl ,setw, hex,dec,oct,set base , setfill,set precission ,ends,flush( )
^branching statement and
^loop
and the if, else, while ,do while,for, exit(), return,switch,go to,continue etc are control statements
Manibulators :- endl ,setw, hex,dec,oct,set base , setfill,set precission ,ends,flush( )
How to install linux (ubuntu) under Windows?
First install windows than goto control panel than goto administrative tools than go computer management and than go disk management click on the disk management option and the screen will be open our computer drives will be open and format one drive or delete logical drive than the screen colour will be green than C.D. of will be put in the driver than reboot the system than we will click next next --------------- many times
The disk of linux is three types -
1.Live c.d.
2. alternate c.d.
3. net install c.d.
The disk of linux is three types -
1.Live c.d.
2. alternate c.d.
3. net install c.d.
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