Bash(bourne again shell)

The bourne again shell(bash) is a user interface for the Linux operating system. Bash can be used to run program, manage files, interact with hardware through the Linux kernel. Shell such as bash are also known as command line interpreters in which a user inputs the commands and it responses to specific command such as ls, cd or cp. Linux is case sensitive. The main advantages of bash is it keeps history of the previous commands and completes a longer command with ease.

Features:-

1.Interactivity And History
Allows to run through previous and current commands use basic keys such as the home, arrow keys, Use the up and down keys to repeat the previous commands.
Other way is if you remember first letter of recent command use the exclamation point(!) followed by character to recall the earlier command.

2. Command Completion
The bash shell allows you to complete command by only partly typing it and using the . For example. To use ypdomainname command to find the NIS domain name for your system, type

#ypd
 
Now when you press tab key it completes the command for you. If there is more than one command starting with ypd, press again, to see list of these commands.