A Unix shell is a command-line interpreter or shell that provides a traditional user interface for the Unix operating system and for Unix-like systems. Users direct the operation of the computer by entering commands as text for a command line interpreter to execute, or by creating text scripts of one or more such commands. Users typically interact with a Unix shell using a terminal emulator, however, direct operation via serial hardware connections, or networking session, are common for server systems.
Source :- https://en.wikipedia.org/wiki/Unix_shell
First thing We are suppose to know is "What is a shell?"
Simple and Short a shell is a program that opens another program
or we can also say a shell is a program that recieves command ( standard input ) either from the keyboard or from a shell script and execute them
TYPES OF SHELL
1. bash = bourne again shell
2. ksh = korne shell
3. csh = c shell
4 sh = Bourne shell
The most commonly used type of shell is the bourne again shell , and that's what we are going to be using through out this short series. Virtuall 90% of commands in the bash shell will work with the Bourne shell (sh or dash ) . I will advice you not to use the c shell because it's too bugy
First and foremost you need a linux/unix operating system if you want to follow us on this course, i will recommend debian linux or perharps you can use ubuntu. they are tons of video online on how to install ubuntu, you can watch them if you don't know how to install ubuntu.
Secondly , incase you don't want to install any linux/unix o.s i will recommend that you should use a unix terminal emulator for windows called cygwin , download it from
here https://www.cygwin.com/ .
Once you get this up and running, we will continue
If you want to know more about the history of linux/unix you can do some google search or check on wikipedia