If

The if statement used when you want to run certain code.

NOTE: Make sure that you tab or put four spaces after the if statement. Python is very sensitive about spaces.

if.py

age = 10

# The == means you are checking if age equals 10
if age == 10:
    print("I'm ", age)

if age > 10:
    print("I'm more than 10")

if age < 10:
    print("I'm less than 10")

Output:

10

Now change the age variable to 9.

Output:

I'm less than 10

Now change the age variable to 11.

Output:

I'm more than 10

More Comparisons

if2.py

age = 11

# The >= means you are checking if age greater than or equal to 10
if age >= 10:
    print("I'm greater than or equal to 10")

if age <= 10:
    print("I'm less than or equal to 10")

Output:

I'm greater than or equal to 10

Now change the age variable to 9.

Output:

I'm less than or equal to 10

Not Equals

if3.py

age = 11

if age != 10:
    print("I'm not equal to 10")

Output:

I'm not equal to 10

Links

• Beginner's Guide

Exercises (5 mins)

1. What is wrong with this program? Can you fix it?

   # Enter a number
   number = input("Enter a number: ")
   
   if number < 10:
       print(number, "is less than 10")
   

2. Complete the following program.

   # Enter your first number
   first_input = input("Enter your first number: ")
   
   # Enter your second number
   second_input = 
   
   # Convert inputs into numbers (first_number, second_number)
   first_number = int(first_input)
   second_number = 
   
   # Check if the first number is smaller than the second number
   if first_number < second_number:
       print(first_number, "is less than", second_number)
   
   # Check if the first number is equal to the second number
   
   # Check if the first number is greater than the second number
   

   Output:

   Enter your first number: 1
   Enter your second number: 2
   1 is less than 2
   
   Enter your first number: 3
   Enter your second number: 2
   3 is greater than 2
   
   Enter your first number: 1
   Enter your second number: 1
   1 is equal to 1