First Python Program

Python, Hello World

On this page

The traditional first program in any programming language

   # Your first Python program
   print("Hello, World!")

Output

Hello, World!

Key Points

print() is a built-in function
Text must be in quotes (“” or ”)
Case-sensitive

Python Syntax

Python syntax refers to the set of rules that define how Python programs are written and structured.

Indentation

Python uses indentation (whitespace) to define code blocks instead of curly braces:

   # Correct indentation
   if 5 > 2:
       print("Five is greater than two!")  # 4 spaces indent

   # Incorrect indentation
   if 5 > 2:
   print("This will cause an error!")

Important: Maintain consistent indentation (4 spaces recommended by PEP 8)

Case Sensitivity

Python is case-sensitive: Variable, variable, and VARIABLE are different

Line Endings

Statements end with newlines (no semicolons needed):

   # Correct indentation
   if 5 > 2:# Preferred
   print("Hello")
   print("World")

   # Also valid but not recommended
   print("Hello"); print("World")

Comments

Comments are explanatory notes ignored by the Python interpreter

Single-line Comments

Start with # symbol:

   # This is a single-line comment
   print("Hello")  # This comment is after code

Multi-line Comments

Use triple quotes (”’ or “””) or multiple # symbols:

 '''
 This is a multi-line
 comment using triple quotes
 '''

 # Alternative using multiple #
 # This is a long comment
 # spanning multiple lines

Comment Uses

Best Practices

Explain complex logic
Document function purposes
Temporarily disable code

Avoid

Obvious statements
Redundant explanations
Outdated comments

Pro Tip: Use comments to write documentation strings (docstrings) for functions and classes