Bash is a shell Command-Line Interface that is very popular in  Unix/ Linux. Like a shell on Unix, Bash is not a simple shell. It  has  lots of features.

One of the features of Bash can be used as a simple calculator. If you are in command-line mode, you do not need to run the calculator application to do a simple calculation process. Simply run the commands like the following in your Bash shell:

admin@smartproteam~$ Echo $ ((2 * 3))
admin@smartproteam~$ Echo $ ((1024 * 1024))
admin@smartproteam~$ Echo $ ((2321 * 3 – 4))