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What are booleans?

Booleans are the simplest data type - they can only be True or False. Think of them as yes/no answers. 
is_logged_in = True
is_admin = False
has_permission = True
Boolean values are True and False with capital letters. Using true or false will cause an error!

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Creating booleans

Booleans often come from comparisons: 
# Direct assignment
is_ready = True

# From comparisons
age = 18
can_vote = age >= 18  # True

score = 75
passed = score > 60   # True

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Comparison operators

These operators compare values and return True or False: 
age = 25

# Equality
print(age == 25)     # True - equals
print(age != 30)     # True - not equals

# Greater/Less than
print(age > 20)      # True - greater than
print(age < 30)      # True - less than
print(age >= 25)     # True - greater or equal
print(age <= 25)     # True - less or equal
Remember: = assigns a value, while == compares values. This is a common source of bugs!

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Common mistakes

# Wrong
is_ready = true   # NameError!
is_done = TRUE    # NameError!

# Right
is_ready = True
is_done = False

# Wrong - this assigns, not compares!
if is_logged_in = True:
    print("Welcome")

# Right - but redundant
if is_logged_in == True:
    print("Welcome")
    
# Best - booleans are already True/False
if is_logged_in:
    print("Welcome")

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What’s next?

Now that you understand data types, let’s learn how to work with them using operators!

Operators

Math, comparisons, and more