Sandiah Notes

What's Kernel
Kernel is hart of Linux O/S. It manages resource of Linux O/S. Resources means
facilities available in Linux. For eg. Facility to store data, print data on printer,
memory, file management etc . Kernel decides who will use this resource, for how
long and when. It runs your programs (or set up to execute binary files) It's
Memory resident portion of Linux. It performance following task :-
l   I/O management
l   Process management
l   Device management
l   File management
l   Memory management



What's Linux Shell
Computer understand the language of 0's and 1's called binary language, In early
days of computing, instruction are provided using binary language, which is difficult
for all of us, to read and write. So in O/s there is special program called Shell. Shell
accepts your instruction or commands in English and translate it into computers
native binary language.
This is what Shell Does for US

You type Your command and shell convert it as
It's environment provided for user interaction. Shell is an command language
interpreter that executes commands read from the standard input device
(keyboard) or from a file. Linux may use one of the following most popular shells
(In MS-DOS, Shell name is COMMAND.COM which is also used for same purpose,
but it's not as powerful as our Linux Shells are!)
Any of the above shell reads command from user (via Keyboard or Mouse) and tells
Linux O/s what users want. If we are giving commands from keyboard it is called
command line interface ( Usually in-front of $ prompt, This prompt is depend upon
your shell and Environment that you set or by your System Administrator,
therefore you may get different prompt ).
NOTE: To find your shell type following command
$ echo $SHELL

Linux Shell Script Tutorial
http://www.freeos.com/guides/lsst/kershell.htm (1 of 5) [17/08/2001 17.42.02]