Bash Variable

Variable is like a container in which you store a value. There are two types of variables-

1. User-defined variables
2. Environment Variables

How to declare a variable in Bash?

variable_name=value

When you assign a value to a variable. Remember one thing, there must be no space between the variable name, equal sign, and the value. If you forget to do so, you will get syntax error.

Note: Variables are case-sensitive, so variable Price is different from the variable price. Also, the variable name must not begin with a digit.

How to access variable value?

There are two ways of accessing the value stored in a variable-

1. Using dollar sign($)- To get a variable value, you prepend $ sign to a variable name i.e. $variable. For example-

   var1=50
   var2=$var1
   echo "The value of var1 is $var1"
   echo "The value of var2 is $var2"

   Output of the above program

   The value of var1 is 50
   The value of var2 is 50

2. Using dollar and curly braces- To get a variable value, use ${variable}. For example-

   var1=50
   var2=${var1}
   echo "The value of var1 is ${var1}"
   echo "The value of var2 is ${var2}"

   Output of the above program

   The value of var1 is 50
   The value of var2 is 50