Writing Your First Python Program

Overview

Writing Your First Python Program is a pivotal step in any developer’s journey. Now that you have Python installed (as discussed in our previous article), this guide will walk you through building and running a simple script. We’ll focus on essential concepts like displaying output, handling variables, and capturing user input, so you can start coding with confidence.

Setting Up Your Workspace

Before you begin, organize your files in a convenient folder—perhaps something like python-projects on your Desktop or in your Documents directory. Python scripts use the .py extension, so you might name your initial file hello_world.py. The choice of editor or IDE is up to you—whether that’s a text editor or a more advanced tool like PyCharm or Visual Studio Code.

The "Hello, World!" Script

The time-honored tradition of coding a "Hello, World!" program holds strong in Python. A minimal example looks like this:

print("Hello, World!")

This line invokes Python’s built-in print function, sending the text "Hello, World!" to the console. While deceptively simple, it marks the start of your Python programming journey.

Running the Program

To run your script:

1. Open a terminal or command prompt.
2. Navigate to the folder containing hello_world.py.
3. Type:

   python hello_world.py

   and press Enter.

You should see:

Hello, World!

Congratulations—you’ve just executed your first Python script!

Exploring Variables and Operations

Python lets you work with variables without explicitly declaring types. For example:

name = "Alice"
print("Hello, " + name + "!")

Here, name is automatically recognized as a string. Python’s dynamic typing makes it quick to prototype ideas. You can also try simple arithmetic:

num1 = 5
num2 = 3
result = num1 + num2
print("The sum is:", result)

Notice how Python infers types at runtime, which is particularly handy for smaller scripts or when you’re moving fast through experimental code.

Interacting with User Input

You can prompt the user for information using the input function:

user_name = input("What is your name? ")
print("It's nice to meet you, " + user_name + "!")

This script will ask for your name and store whatever you type into user_name. You can later reuse that data to personalize output or perform various tasks.

Comments and Clarity

As your code evolves, maintaining clarity is essential. Python uses the hash (#) symbol to denote comments:

# This line greets the user
print("Hello!")

Comments help you (and others) understand the purpose behind certain lines or logic. They are ignored during execution, so use them liberally to explain your thought process.

Fun Facts and Helpful Hints

• Python REPL: Launch an interactive Python session by typing python (or python3) in a terminal. You can experiment with code snippets line by line, which is great for learning.
• IDE Support: Editors like PyCharm, VS Code, and Jupyter Notebook can boost your productivity by offering features such as autocompletion, debugging, and built-in terminals.
• Whitespace Matters: Python uses indentation to structure code blocks. Make sure you’re consistent—typically four spaces—when you indent lines after a colon (:).

Conclusion

You’ve taken your first steps into Python by creating a classic "Hello, World!" program, working with variables, user input, and fundamental output. These building blocks will serve you well as you delve deeper into Python’s rich ecosystem. In upcoming articles, we’ll explore the language’s indentation rules, control flow constructs, and other essential topics that transform basic scripts into sophisticated applications.