➡What is Kernel

The kernel is a computer program that is the core of a computer’s operating system, with complete control over everything in the system.

➡What is Shell

A shell is a special user program that provides an interface for the user to use operating system services. Shell accepts human-readable commands from a user and converts them into something that the kernel can understand. It is a command language interpreter that executes commands read from input devices such as keyboards or from files. The shell gets started when the user logs in or starts the terminal.

➡What is Linux Shell Scripting?

A shell script is a computer program designed to be run by a Linux shell, a command-line interpreter. The various dialects of shell scripts are considered to be scripting languages. Typical operations performed by shell scripts include file manipulation, program execution, and printing text.

➡Day 4 - Task

1. Explain in your own words and examples, what is Shell Scripting for DevOps.

   The shell is the Linux command line interpreter. It provides an interface between the user and the kernel and executes programs called commands. For example, if a user enters ls then the shell executes the ls command. The shell can also execute other programs such as applications, scripts, and user programs (e.g., written in c or the shell programming language).

2. What is#!/bin/bash?can we write#!/bin/shas well?

   #!/bin/bash or #!/bin/sh in script file is known as a shebang line or hashbang line. It is used to write on top of the script file.

   #!/bin/bash : It is used for enabling bash shell as an interpreter to execute the script. In maximum systems by default bash shell is used.

   #!/bin/sh : It is used for the default shell of the system to execute the script which might be different shells like Bourne, and Korn shells.

3. Write a Shell Script which printsI will complete #90DaysOofDevOps challenge

   

4. Write a Shell Script to take user input, input from arguments, and print the variables.

   

   

5. Write an Example of If else in Shell Scripting by comparing 2 numbers

   

   

   Thank you for reading! :)