In Ruby, you can write multiple variable types based on the following usage.

  • Global Variables
  • Class Variables
  • Instance variables
  • Constant Variables

Global Variables in Ruby

Global variables are declared with $.

These are available across all modules and classes in the same file and the scope is Global.

$company ="w3schools.io""
class Employee{
    def display
        puts "display employee company $company"
    end

}
class Department{
    def display
        puts "display department company $company"
    end

}

Output:

display employee company w3school.io
display employee department w3school.io

Instance variable

The instance variable starts with @ and variable name.

Ruby class variable

a class variable declared with @@