Comments are notes for humans. Python ignores them completely. Use the # symbol to start a comment: python # This is a comment print("Hello") # This prints Hello Everything after # on that line is ignored.
Comments help you remember why you wrote something a certain way. They also help others understand your code.
Don't comment obvious things like x = 5 # set x to 5. That adds noise without value. Comment the "why", not the "what". Good: # Convert to cents to avoid floating point errors.