University of Hawaii at Manoa
What is a shell?
A shell is a program which provides a user interface. With a shell, users can type in commands and run programs on a Unix system. Basically, the main function a shell performs is to read in from the terminal what one types, run the commands, and show the output of the commands.
What's so good about C Shell?
The C shell was written by Bill Joy at the University of California at Berkeley. His main intent for writing the C shell was to create a shell with C language-like syntax.
What can one do with C Shell?
The main use of the C shell is as an interactive shell, but one can write programs using the C shell. These programs are called shell scripts.