Why we assigned the the value of variable "option" 1 before loops?
<p>I'm a new to programming and I chose python as my first language because its easy. But I'm confused here with this code:</p>

<pre><code>option = 1 
while option != 0:
    print "/n/n/n************MENU************" #Make a menu
    print "1. Add numbers"
    print "2. Find perimeter and area of a rectangle"
    print "0. Forget it!"
    print "*" * 28

    option = input("Please make a selection: ") #Prompt user for a selection      
    if option == 1: #If option is 1, get input and calculate 
        firstnumber = input("Enter 1st number: ")
        secondnumber = input("Enter 2nd number: ") 
        add = firstnumber + secondnumber
        print firstnumber, "added to", secondnumber, "equals", add #show results  

    elif option == 2: #If option is 2, get input and calculate
        length = input("Enter length: ")
        width = input("Enter width: ")
        perimeter = length * 2 + width * 2
        area = length * width
        print "The perimeter of your rectangle is", perimeter #show results       
        print "The area of your rectangle is", area

    else: #if the input is anything else its not valid
        print "That is not a valid option!"
</code></pre>

<p>Okay Okay I get every thing below the <code>Option</code> variable. I just want to know why we assigned the value of <code>Option=1</code>, why we added it on the top of the program ,and what is its function. Also can we change its value. Please make me understand it in simple language as I'm new to programming.</p>
