Variables in shell script

Variables are use to assign the value of data types such as integer, float, string, etc.   

In shell scripting no need to specify types for your variable.

Create integer variable
     In C language

           int a = 10;
     In shell script

           a=10

You should not leave any space between equal sign

       a = 10(it will not work)

To access the variable use dollar($) symbol.

Script:

#!/bin/sh

my_variable=10
echo "my variable is $my_variable"my_variable="mystring"
echo "my variable is $my_variable"

Output:

my variable is 10

my variable is mystring

If you want to read value to variable from user you have to use 'read' keyword

Script:

#!/bin/bash

echo -n "Enter any value : "
read var
echo "Entered value is $var"

output:

Enter any value : 100 
Entered value is 100