Syntax & Indentation

This is probably the first thing you need to get used to, coming from JS/TS.

In JavaScript, { } marks a block:

if (age >= 18) {
  console.log('Adult');
}

In Python, a : starts a block, and indentation defines what belongs inside it. There are no curly braces.

if age >= 18:
    print("Adult")

Multiple lines can belong to the same block:

if age >= 18:
    print("Adult")
    print("Can vote")

print("Done")

Here's how that breaks down:

if block
├── print("Adult")
└── print("Can vote")

outside block
└── print("Done")

Python usually uses 4 spaces for indentation.

# ❌ Wrong — missing indentation
if age >= 18:
print("Adult")

# ❌ Also wrong — inconsistent indentation
if age >= 18:
    print("Adult")
        print("Can vote")

# ✅ Correct
if age >= 18:
    print("Adult")
    print("Can vote")