Installing Python

In the last lesson you saw why Python is worth learning. Now you need it on your own computer so you can actually run code. Let’s get Python installed and make sure it works.

🤔 Why do we even need to install Python?

When you write Python code, that code is just text. Your computer cannot run it on its own. It needs a program that reads your code and runs it. That program is called the Python interpreter.

So installing Python means putting that interpreter on your machine. Here is the situation on most computers:

• Windows usually comes with no Python at all. You have to install it yourself.
• macOS does not ship with a ready-to-use Python 3 anymore. You install your own.
• Linux often has Python 3 already, but it may be an older version. You may want a newer one.

Either way, the goal is the same. Get a recent Python 3 working, so when you type python your computer knows what to do.

🔎 First, check if you already have it

No point installing twice. Before anything else, open your terminal and check. On Windows that is Command Prompt or PowerShell. On macOS or Linux that is the Terminal app.

This command asks Python to print its version number.

python --version

If that prints nothing useful, try this one instead. On macOS and Linux the command is often python3.

python3 --version

Python 3.13.1

If you see a version that starts with 3., you already have Python 3. You can skip ahead to the “check it worked” part. If you see an error like “command not found”, or a version that starts with 2., follow the steps for your system below.

🪟 Installing on Windows

On Windows you also get a helper called the py launcher. If python ever acts strange, you can use py instead. For example, py --version does the same check.

🍎 Installing on macOS

The simplest way is the official installer, the same site as before.

If you already use Homebrew, the package manager for macOS, you can install Python with a single command instead. This downloads and sets up the latest Python 3.

brew install python

🐧 Installing on Linux

Most Linux systems already have Python 3. If yours does not, or it is too old, you install it through your system’s package manager. On Ubuntu or Debian, this command installs Python 3 and pip (the tool for adding extra Python packages).

sudo apt update
sudo apt install python3 python3-pip

On Fedora, the command looks like this instead.

sudo dnf install python3 python3-pip

✅ Check that it actually worked

No matter which system you used, finish with the same check. Open a fresh terminal and ask for the version.

python --version

If that does not work, try python3 --version. You should see a line starting with Python 3.

Now let’s run real Python code. This command runs a tiny program right from the terminal that prints a message.

python -c "print('Python is working!')"

Python is working!

If you see that message, Python is installed and running. That is the whole goal of this lesson.

🐍 What about pip?

You will hear about pip a lot. pip is the tool that installs extra Python packages, the ready-made tools other people have written. The good news is you do not install it separately. Modern Python 3 comes with pip already inside it.

You can check it the same way you checked Python.

pip --version

If pip does not work, try pip3 --version. We will use pip properly in a later lesson, so don’t worry about it for now. Just good to know it is there.

⚠️ Common Mistakes

A few small things trip people up during install. Watch for these.

• Forgetting the PATH checkbox on Windows. This is the number one reason python “does not work” after install. Run the installer again and turn it on.
• Using python when your system wants python3. On many Macs and Linux machines, plain python may be missing or point to old Python 2. Use python3 and pip3 there.
• Checking in an old terminal window. A terminal that was already open does not see the new install. Close it and open a new one.
• Installing Python 2. It is dead. Always grab the latest Python 3.

✅ Best Practices

• Always install the latest Python 3 from the official site, python.org. It is safe and up to date.
• Tick “Add to PATH” on Windows. It makes everything afterward easier.
• Open a fresh terminal to test. It avoids the “it does not work” confusion.
• Remember python3 and pip3 as backups on Mac and Linux if the plain commands fail.

🧩 What You’ve Learned

You now have Python on your machine. Here is the short version.

• ✅ Python code needs the Python interpreter installed to run.
• ✅ You download Python 3 from the official site python.org, or use a package manager like Homebrew or apt.
• ✅ On Windows, ticking Add python.exe to PATH is the key step.
• ✅ You check the install with python --version (or python3 --version).
• ✅ pip comes bundled with modern Python 3, so you do not install it separately.

🚀 What’s Next?

Python is installed and working. Next, let’s actually run some Python code and see the different ways to do it.

Running Python Programs