Your First Python Program — Hello, World!

Remember your first day at a new job? You walked in, maybe a little nervous, and at some point someone asked you to introduce yourself to the team. "Hi, I'm Alex. I'm the new junior developer." Simple sentence. Huge moment. You existed in that room before, but now the room knew you existed.

Your first program does the same thing. It's your code introducing itself to the world — saying "I'm here, I'm running, and I work." It's a tradition as old as programming itself, and today you're joining it.

The "Hello, World!" Tradition

In 1972, Brian Kernighan wrote a small example program in a tutorial for the B programming language. It printed the words "hello, world" to the screen. It wasn't the first such program, but it stuck. The phrase became a cultural touchstone — the universal first step every programmer takes when learning a new language.

Today, writing "Hello, World!" is essentially a rite of passage. It means:

• Your language is installed correctly
• Your editor is working
• You can write code, run it, and see the result
• You are, officially, a programmer

It sounds small. It isn't.

Writing the Program

Open VS Code (or IDLE), create a new file called hello.py, and type this:

print("Hello, World!")

That's it. That's the whole program.

Now let's break down every single piece of that one line, because each part matters.

What Each Part Does

• print is a function — a named action that Python knows how to perform. Think of it like pressing a button labeled "display this on screen."
• The parentheses are how you pass information to a function. Everything inside them is what print will work with.
• The quotes tell Python "this is text, not code." Without them, Python would think Hello is a variable name and get confused.

Running the program in VS Code:

1. Open the terminal: View → Terminal (or press Ctrl+`)
2. Type python hello.py and press Enter
3. You should see:

Hello, World!

One line in, one line out. Clean, simple, perfect.

Modifying It: Make It Personal

Now that it works, let's make it yours. Change the file to:

print("Hello, World!")
print("My name is Alex.")
print("I am learning Python.")

Output:

Hello, World!
My name is Alex.
I am learning Python.

Each print() call creates a new line of output. You can have as many as you want. Notice Python runs them top to bottom, in order — just like our chef following a recipe.

Comments: Notes for Humans

Here's something important: you can leave notes inside your code that Python completely ignores. These are called comments, and they start with a # symbol.

# This is my first Python program
# Written on my first day of learning

print("Hello, World!")  # This line prints the greeting
print("My name is Alex.")

Comments are for people, not the computer. Python skips over anything after a # on a line. Use them to:

• Explain why you're doing something
• Leave a note for your future self (trust me, you'll thank yourself)
• Temporarily disable a line of code without deleting it

Good habit: Write comments like you're leaving notes for someone who has no idea what your code is supposed to do. Because six months from now, that someone might be you.

Your Second Program: A Simple Calculator

Let's level up. Here's a program that does some real work:

# Simple calculator
num1 = 10
num2 = 5
result = num1 + num2
print("The answer is:", result)

Line by line:

Output:

The answer is: 15

Notice that print() here takes two things separated by a comma: a piece of text and a variable. Python prints both, with a space between them. This is how you mix fixed text with variable data.

Common Errors (and How to Fix Them)

Everyone makes these mistakes. Everyone. Here's what they look like and what to do:

Error 1: Missing quotes

print(Hello, World!)

Error message:

  File "hello.py", line 1
    print(Hello, World!)
                      ^
SyntaxError: invalid syntax

Fix: Add quotes around the text — print("Hello, World!")

Error 2: Misspelling print

Print("Hello, World!")

Error message:

NameError: name 'Print' is not defined

Fix: Python is case-sensitive. print must be all lowercase — print("Hello, World!")

Error 3: Missing closing parenthesis

print("Hello, World!"

Error message:

  File "hello.py", line 1
    print("Hello, World!"
         ^
SyntaxError: '(' was never closed

Fix: Every opening ( needs a closing ) — print("Hello, World!")

Reading error messages is a skill. Don't panic when you see red text. Look for the line number (it tells you where the problem is) and the error type (it tells you what the problem is). With practice, you'll read error messages as naturally as reading a sentence.

Putting It Together: A Personal Introduction Program

# My personal introduction
# This program introduces me to the world

print("=" * 30)          # Print a decorative line
print("Hello, World!")
print("My name is Alex Johnson.")
print("I live in New York City.")
print("I am learning Python programming.")
print("=" * 30)

Output:

==============================
Hello, World!
My name is Alex Johnson.
I live in New York City.
I am learning Python programming.
==============================

The "=" * 30 is a fun trick — Python repeats the = character 30 times. More on this in a later lesson, but it shows you that even small programs can have style.

Your Challenge

Write a program that prints:

1. Your full name
2. Your city or country
3. One thing you're hoping to build with Python

Save it as introduction.py and run it. If it displays your information without any errors — congratulations. You're a Python programmer.

Seriously, do the challenge. Reading about programming and writing code are completely different experiences. Your fingers need to type the code. Your eyes need to see it run. That's how the knowledge sticks.

Key Takeaways

• print() displays text and values to the screen
• Text (strings) must be wrapped in quotes — single ' or double " both work
• Comments start with # and are ignored by Python — they're notes for humans
• Python is case-sensitive: print works, Print does not
• Error messages are helpful — they tell you the line number and what went wrong
• Every print() call outputs on its own line