When you type in commands at the Unix command line, you are using one on several command line shell programs.
A shell is simply the word that we use for a program that accepts command line input for the Unix operating system.
The most commonly used shell in 2016 is the bash shell.
Bash was first developed by a programmer named Brian Fox, who happens to live in Santa Barbara.
- You can read more about Brian Fox at his Wikipedia Page
- You can also watch a video of a talk by Brian Fox as part of the UCSB CS Dept Array of Talks Series
Shell Scripting
Bash also provides control structures such as if, while, for, etc., as well as the ability to define functions—and thus can be used for programming. The power of bash programming is that the basic Unix commands to copy, move, delete and rename files, as well as listing and creating directories (cp,mv,rm,mkdir,rmdir, ls etc.) can be put into these “bash programs” as commands.
Programs that are written with bash are called shell scripts or bash scripts.
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