Are you planning to learn shell? Let's have a brief introduction onto the subject

What is Shell?

An operating system consists of various components, but its two prime components are:

•    Kernel

•    Shell

An operating system has an innermost region which comprises Kernel. It is basically at the nucleus of a computer. It leads to a proper channel of communication so that there is no error in information sharing between hardware and software. 

A shell is firstly the outermost part of the operating system in the Linux operating system, Shell majorly gathers input in the form of commands which is further processed and thus output is created. It is an interface through which a user works on the programs, commands, and scripts. A shell is actually accessed by a terminal which runs it.

When you run the terminal, the Shell issues a command prompt (usually $), where you can then type your input. The command is then executed when you hit the Enter key. The output or result is thereafter displayed on the terminal.

The Shell wraps around the delicate interior part of an operating system protecting it from accidental damage. Hence the name Shell.

Types of Shell

There are two main types of shells in Linux:

1. The Bourne Shell: The command prompt for this shell is $ and its derivatives are listed below:

•    POSIX shell also is known as sh

•    Korn Shell also has known as tsh

•    Bourne Again Shell which is popularly known as bash is well known.

2. The C shell: The command prompt for this shell is % and its subcategories are:

•    C shell termed as csh

•    Tops C shell which is shortly termed as tcsh

What is Shell Scripting?

Shell scripting is writing a series of commands for a shell to execute. It can combine lengthy and repetitive sequences of commands into a single and simple script, which can be stored and executed at any given point of time. This reduces the efforts required by the end-user.

Let us understand the steps for creating a Shell Script:

• Create a file using a vi editor (or any other editor). 
• Name script file with extension .sh
• Start the script with #! /bin/sh
• Write some code
• Save the script file as filename.sh
• For executing the script type bash filename.sh
•  "#!" is an operator known as shebang which directs the script to the interpreter location. So, if we use"#! /bin/sh" the script gets directed to the bourne-shell.

What are Shell Variables?

As discussed earlier, Variables store data in the form of characters and numbers. Similarly, Shell variables are for the purpose of storing all data which can be done via Shell.

A kernel is the actual nucleus of the operating systems, and it communicates between hardware and software. Shell is a programming language which interprets user commands through CLI like Terminal. The Bourne shell and the C shell are the most used shells in Linux. 

Shell scripting is writing basically a series of commands for the shell to execute. A number of various strings can be stored under Shell variables. Shell scripting can help you to create complex programs containing conditional statements, loops, and functions.

Learning shell and its scope:

Ranked No. 14 among the 25 skills that can get you hired in upcoming by LinkedIn, Unix and Shell Programming, are among the top skills that employers are seeking in their prospective employees this year. According to ZDnet.com, 45% of all the Unix hiring companies in the United States for 2015 was for shell scripting. There is a high upsurge of demand for Unix Shell Scripting professionals.

Reason #1: The Robust Scope of Shell Scripting

The topmost reason for the popularity of Unix Shell Scripting is its robust scope. It is a super powerful programming method that can help you to learn the command-line better, save plenty of time, and get rid of tedious file management tasks.

Reason #2: Promising Career Progression

While the demand continues to grow for Unix shell scripting talent, there also remains a shortage of experienced professionals in the market. There are unlimited career advancement opportunities for developers and system administrators who are skilled in Unix Shell Scripting.

Reason #3: Salary Growth

According to Indeed.com, a professional with Unix Shell Scripting skill can get an average pay of $97,000 in the United States. Apart from this, average Unix Shell Scripting salaries for job postings nationwide are 68% higher than average salaries for all job postings nationwide.

Some few job roles that you can bag with Unix skills are:

•    Systems Engineer- Unix/ Linux

•    Software Engineer

•    Unix/Linux Engineer Job

•    System Administrator

So are you ready to take your career to the next level?