Question

If you don’t already have Python 3 installed on your computer, do it now. Read Appendix B for the details for your computer system.

Short answer

Download and install Python 3 from the official website, following the on-screen instructions.

Step-by-step solution

Check Existing Installation

Begin by checking if Python 3 is already installed on your system. Open a command line interface (Command Prompt for Windows, Terminal for macOS/Linux) and type `python --version` or `python3 --version`. If you see a version number that starts with 3.x, Python 3 is installed.

Visit Python's Official Website

Go to the official Python website at https://www.python.org. Navigate to the 'Downloads' section. The site will automatically offer a download link compatible with your operating system.

Download the Installer

Click the download link to get the Python 3 installer for your operating system. The installer is typically named something like `python-3.x.x.exe` for Windows, or `python-3.x.x.pkg` for macOS.

Run the Installer

Locate the downloaded installer file and double-click it to run. For Windows, this will be a step-by-step setup wizard. Make sure to check the option 'Add Python 3.x to PATH' during installation. For macOS, follow the installer prompts and provide your password when prompted.

Verify the Installation

Once installation is complete, open a new command line window and check if Python 3 is correctly installed by typing `python --version` or `python3 --version` again. Ensure it returns a version number starting with 3.x.

Key concepts

Operating System Compatibility

Your computer's operating system (OS) determines which version of software you should download and install. When it comes to installing Python 3, compatibility with your OS is crucial for a smooth installation process.
Python 3 is compatible with major operating systems like Windows, macOS, and various distributions of Linux. Each system requires a different installer format:

• For **Windows**, the installer is typically a `.exe` file.
• For **macOS**, the installer will be in `.pkg` format.
• For **Linux**, Python is often installed using package managers like `apt` or `yum`.

Make sure that you choose the correct installer for your specific OS version to avoid installation issues. If you're not sure, visit the Python official website, which will automatically suggest the best installer based on your operating system.
This ensures that all the necessary components are correctly set up to interact seamlessly with your OS environment.

Command Line Interface

The Command Line Interface (CLI) is a powerful tool for interacting directly with your computer's operating system and software. It allows you to enter text commands to perform specific tasks such as installing software like Python.
Using a CLI might seem daunting if you're not familiar with it. However, it's quite straightforward once you get the hang of it. Here’s how you can use the CLI to check Python installation:

• On **Windows**, you'll use the Command Prompt. Type `cmd` into the search bar to open it.
• For **macOS** and **Linux**, you’ll use the Terminal, which can be found in the Utilities folder or quick-launched.

Once opened, you can check if Python is installed by typing `python --version` or `python3 --version`. If Python 3 is installed, the command will return a version number beginning with 3.x.
Understanding how to navigate and execute commands in the CLI is an essential skill, providing you with greater control over programming environments and system resources.

Python Official Website

The official Python website is your primary resource for downloading and installing Python. Accessible at [python.org](https://www.python.org), it contains everything you need to get started with Python from installation files to various helpful guides.
When you navigate to the 'Downloads' section, the Python site automatically detects your operating system and recommends the appropriate version for you. This feature eliminates the guesswork from selecting the correct file for your setup.
Besides downloads, the website offers extensive documentation and tutorials to help you learn Python programming. You’ll also find news updates, community forums, and links to Python-related events.
Using official resources ensures that you get the most secure and up-to-date version of Python. It also provides confidence in the integrity of the software you are installing on your machine. Remember to verify your download by checking the file’s integrity, which is usually detailed on the download page itself.