Installation

You do not strictly need to install anything to work through this course: every code block on every page runs in your browser with no setup required. That said, sooner or later you will want a local Python so you can run scripts, install third-party libraries, and integrate with your editor.

Picking a version

Always install the latest stable Python 3 (3.13 at the time of writing) unless a specific project pins you to an older version.

Which install method should you use?

Installing Python

Pick the option that matches your operating system.

macOS

The Python that ships with macOS is for the system, not for you. Use one of:

• python.org installer. Download from python.org/downloads and run the .pkg. This is the simplest option for most users.
• Homebrew. brew install python installs the latest 3.x and adds python3 and pip3 to your PATH.
• pyenv. brew install pyenv then pyenv install 3.13.2. This lets you switch versions per project and is the gold standard for Python developers juggling multiple projects.

Windows

• Download the installer from python.org/downloads.
• Check "Add python.exe to PATH" on the first screen of the installer. This is the single most common gotcha. Without it, the python command will not work from the terminal.
• Alternatively, install from the Microsoft Store, which keeps Python updated automatically and handles the PATH for you.

Linux

Most distributions ship a recent Python in their package manager:

# Debian/Ubuntu
sudo apt install python3 python3-pip python3-venv

# Fedora
sudo dnf install python3 python3-pip

# Arch
sudo pacman -S python python-pip

For full version control, install pyenv and let it manage multiple side-by-side interpreters:

# Install pyenv via its install script
curl https://pyenv.run | bash

# Add to your shell config (.bashrc, .zshrc, etc.)
export PATH="$HOME/.pyenv/bin:$PATH"
eval "$(pyenv init --path)"
eval "$(pyenv init -)"

# Install a Python version
pyenv install 3.13.2
pyenv global 3.13.2

Verifying the install

Open a terminal and run:

python3 --version
pip3 --version

You should see something like Python 3.13.2 and a matching pip version. On Windows the commands are python and pip (without the 3 suffix).

The REPL

Running python3 with no arguments drops you into the REPL (read, eval, print, loop), an interactive interpreter:

$ python3
Python 3.13.2 (main, ...) on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> 2 + 2
4
>>> name = "Ada"
>>> f"Hello, {name}!"
'Hello, Ada!'
>>> exit()

The REPL is perfect for exploring a library or testing one-liners. For longer experiments, save your code to a file like script.py and run it with python3 script.py.

Running code in the browser

Every executable block in this course runs in your browser — no setup required. This is powered by real Python 3.13 with NumPy, Pandas, Matplotlib, and Plotly preinstalled. Try it:

Test your knowledge

Next: write your first program.