The first question your code ever asked

The problem...

Your code does exactly what you tell it. Every time. Without question.

You print a name — it prints the name. You calculate a number — it calculates the number. It doesn't care if the input makes sense. It doesn't care if something's wrong. It just runs.

That's a script. Not a program.

The idea!

What if your code could check something before acting?

What if it could say: "Only do this if the condition is true."

That's exactly what if does.

The syntax

if condition:
    # code runs only if condition is True

Two things to notice:

The if line ends with a colon :. The code inside is indented — 4 spaces. That indentation tells Python: "this belongs to the if."

Your first if

temperature = 35

if temperature > 30:
    print("It's hot outside.")

Python checks the condition: is temperature > 30 true?

Yes — so it runs the print. Simple as that.

What if the condition is false?

temperature = 20

if temperature > 30:
    print("It's hot outside.")

Nothing happens. No output. No error. Python checks the condition, sees it's false, and skips the block entirely.

That's the power — code that only runs when it should.

Conditions you can use

x = 10

if x > 5:       # greater than
    print("big")

if x == 10:     # equal to
    print("exact")

if x != 7:      # not equal to
    print("not seven")

if x >= 10:     # greater than or equal
    print("at least ten")

Any expression that returns True or False works as a condition.

A real example

score = 85

if score >= 60:
    print("You passed.")

Clean. Readable. Purposeful. Your code is no longer just calculating — it's making a decision.

Heads up!

• The if line always ends with :
• The block inside must be indented — 4 spaces
• == checks equality — = assigns a value. Not the same thing.
• If the condition is false, the block is skipped — no error

The mindset shift

Stop thinking: "My code runs everything."

Start thinking: "My code runs what makes sense."

What you should understand now

• if runs a block of code only when a condition is True
• The condition is any expression that evaluates to True or False
• The colon : and indentation are not optional — they're part of the syntax
• If the condition is false, Python skips the block and moves on