What Is Python? A Plain-English Guide

Python is one of the most popular programming languages in the world — and the language most AI research and data work is done in. If you're building with AI tools, you'll meet it sooner or later, even if your app is written in something else.

The short version

Python is a general-purpose programming language known for being easy to read. Its code looks closer to plain English than most languages, which makes it popular with beginners, scientists and anyone who wants to get something done without fuss.

It was created by Guido van Rossum and first released in 1991. It's free and open source, and runs on Windows, Mac and Linux.

What Python looks like

books = ["Dune", "Emma", "Beloved"]

for book in books:
    print(f"I want to read {book}")

if len(books) > 2:
    print("That's a lot of reading!")

A few things that make Python distinctive:

Indentation matters. The spaces at the start of a line decide which code belongs inside the for loop or if. Other languages use braces { } for this.
Little punctuation. No semicolons, fewer brackets.
Readable built-ins. len(books) is the length of the list; print prints.

What Python is used for

AI and machine learning. Most AI research, model training and data science happens in Python, using libraries like PyTorch, NumPy and pandas.
Data analysis. Cleaning spreadsheets, making charts, crunching numbers in Jupyter notebooks.
Web backends. Frameworks like Django, Flask and FastAPI power the server side of many websites and APIs.
Automation and scripts. Renaming 5,000 files, scraping a website, sending a daily report — small jobs Python is perfect for.
Tooling. Many command-line tools and devops scripts are written in Python.

What it's not used for: code that runs in a web browser. Browsers run JavaScript. A Python app can still have a website — the Python runs on the server, and the browser gets HTML and JavaScript. (Frontend vs backend)

Running Python

You install Python from python.org (Macs and Linux often include a version already). Then:

python3 hello.py

On Windows the command is often python or py instead of python3.

Packages and virtual environments

Python's package manager is pip (pip install requests), and a newer, much faster tool called uv has become very popular. Each project should have its own virtual environment so its packages don't clash with other projects'. That's one of the first things that trips up beginners — see Python virtual environments explained.

Versions

Always use Python 3. Python 2 reached end of life in 2020, and old tutorials using print "hello" (without brackets) are Python 2. A new version of Python 3 comes out every October; any recent 3.x release is fine for new projects.

Should your app use Python?

Python is a great choice when your app:

does data processing or AI work beyond calling an API,
needs a library that only exists in Python,
is mostly scripts and automation,
is built by someone who already knows Python.

If your app is mainly a web interface, JavaScript/TypeScript lets you use one language for both the browser and the server, which is why many AI app builders default to it. See Python vs JavaScript for a direct comparison.

Why AI coding tools are good at Python

There's an enormous amount of public Python code, and it's very readable — so AI models write it well. Python apps also tend to be easy to review even if you're not a programmer, because the code reads almost like instructions.

The summary

Python is a readable, general-purpose language, released in 1991, free and open source.
It dominates AI, data science and automation, and powers many web backends.
It doesn't run in browsers; for websites, it runs on the server.
Use Python 3, a virtual environment per project, and pip or uv for packages.

EasySpawn servers come ready for Python as well as Node.js and other stacks, with pip and uv available and your installed packages kept on persistent storage between sessions. See how it works or join the waitlist.

What Is Python? What It's Used For and Why AI Loves It