If you open the code behind a banking app, a movie recommendation, a rocket launch dashboard and a school marks sheet, there is a good chance that at least one of them was written in Python. It is the language that a student can pick up in a weekend, and a data scientist can still use ten years later. That range is rare.
Python is a high level, general purpose programming language that is known for code that reads almost like plain English. It was created in the early 1990s, it is free to use, and it runs on Windows, Mac and Linux. In October 2026, the TIOBE index, which ranks languages by how widely they are used, still places Python at number one.
In this guide, we explain what Python is, where it came from and why it has the name it has. We go through its main features, with a short example of each, and its scope, which means the kinds of work it is used for. We then look at the libraries used for data science and visualization, compare Python with other languages, and say plainly where it is weak. We finish with a simple plan to start learning.
Python is a general purpose, high level, interpreted programming language. Each of those words has a meaning.
Python supports several styles of programming, including procedural, object oriented and functional. That means you can start with simple step by step scripts, and later move to classes and larger designs, in the same language. The official Python FAQ describes it as an interpreted, interactive, object oriented language that combines remarkable power with very clear syntax.

Here is the classic first program. It is a single line.
In many other languages, the same program takes four or five lines of setup. That is one reason Python is popular with beginners. Here is a slightly bigger example, with a list and a decision:
Notice that Python uses indentation, the spaces at the start of a line, to show which lines belong together. There are no curly brackets. This forces tidy code, and it is a big part of why Python is easy to read.
| When | What happened |
|---|---|
| December 1989 | Guido van Rossum, working at CWI in the Netherlands, starts Python as a holiday project, over the Christmas break |
| February 1991 | He posts the first public version to the USENET newsgroups |
| January 1994 | Python 1.0 is released |
| October 2000 | Python 2.0 is released, adding features such as list comprehensions |
| December 2008 | Python 3.0 is released. It fixes old design problems, and it is not fully compatible with Python 2 |
| 2020 | Python 2 reaches end of life. Support ends on 1 January 2020, and the final release, 2.7.18, comes in April 2020 |
| October 2026 | Python 3.15 is released on 9 October 2026 |
Many people think the name comes from the snake. It does not. Guido van Rossum wanted a name that was short, unique and slightly mysterious, and he named the language after Monty Python’s Flying Circus, a British comedy show from the 1970s.
Python is open source. The Python Software Foundation, a non profit, holds the rights to it. The license lets you use Python freely, even in commercial products, as long as you keep the copyright notices. New features are proposed in public documents called PEPs, and a new feature release comes out every 12 months. If your company plans to ship Python inside a product, have your legal team read the PSF license text itself.
These are the features that matter most. Each one is explained here, with a short example.
The syntax is short and close to English. The program you saw above is clear even to a beginner. Less typing and fewer symbols mean fewer places to make a mistake.
Python first compiles your code to a simpler form called bytecode, and then the interpreter runs the bytecode. You do not see this step or manage it. You can look at the bytecode of a function with the dis module:
The exact names and the extra lines change between Python versions, so your screen may look a little different. The point is that your code becomes a list of small steps, and Python runs them one by one.
You do not declare the type of a variable. Python works it out from the value, and you can change it later.
The same program runs on Windows, Mac and Linux, as long as Python is installed. The official FAQ says Python is portable, and runs on many Unix systems including Linux and macOS, and on Windows.
Python costs nothing, and its source code is open. A very large community builds extra tools for it and shares them for free.
You can write a plain loop, a functional one line, or a class, and all three are normal Python.
Python is said to come with batteries included. Its standard library has ready made tools for maths, dates, files, text, the internet and more, and you do not install anything extra to use them.
You can build desktop windows and buttons with Python. The standard library has Tkinter, and outside libraries such as PyQt and wxPython add more.
The thing that makes Python stand out is the number of libraries built on top of it. They are downloaded from the Python Package Index, and installed with pip. More on this below.

Python has a very wide scope. Here is a view of the kinds of work done in each area.
| Area | What Python is used for |
|---|---|
| Data science and analysis | Cleaning data, finding patterns, building reports, with libraries like pandas and NumPy |
| Machine learning and AI | Training and using models, with libraries like scikit learn |
| Web development | Websites and back end services, with frameworks such as Django and Flask |
| Automation and scripting | Renaming files, sending emails, collecting data from websites, filling reports |
| Desktop and GUI software | Windows, buttons and forms, with Tkinter or PyQt |
| Testing and DevOps | Writing tests, managing servers, and gluing tools together |
| Education | Many schools and universities teach Python first, because it is easy to read |
| Science and research | Maths, statistics and simulations, with SciPy and others |
The official Python FAQ names Google, Yahoo and Lucasfilm among the companies that use Python inside their systems, and says several Linux distributions, notably Red Hat, wrote part or all of their installer and system tools in Python.
Two well known sources give a current picture.
These are two different measures, so they do not contradict each other. TIOBE counts how much a language is searched for and discussed online. The Stack Overflow survey asks developers what they use.
A video is a good way to see Python running for the first time.
Python does not come with built in libraries for machine learning. The libraries below are separate downloads, and you install them with pip. If you try to use one that you have not installed, Python stops with an error:
Only two of the seven libraries are for visualization. Here they are, grouped by what they actually do.
| Library | What it is for | Group |
|---|---|---|
| NumPy | Fast arrays and maths on numbers | Data and maths |
| SciPy | Scientific computing, built on NumPy | Data and maths |
| pandas | Tables of data, called DataFrames | Data analysis |
| statsmodels | Statistical models and tests | Data analysis |
| scikit learn | Machine learning algorithms | Machine learning |
| Matplotlib | 2D and 3D charts | Visualization |
| Seaborn | Statistical charts, built on Matplotlib | Visualization |
NumPy gives Python fast arrays and the maths to work on them. Almost every other library in this list is built on it, and it is where most data work starts.
SciPy adds scientific tools on top of NumPy: statistics, optimisation, signal processing and more. For example, it can tell how strongly two sets of numbers move together.
A value close to 1 means the two move together very strongly.
The name is written as one word, in lower case. It is used for statistical models and tests, such as regression with full statistical reports.
pandas is a library for working with tables of data. Here it finds the average mark in each course:
Scikit learn is the main library for classic machine learning. It covers classification, regression, clustering and more. Here is a tiny model that learns the link between study hours and marks, and predicts the mark for 6 hours:
Matplotlib is the main library for drawing charts in Python, including line, bar, pie, scatter and 3D plots. See our Matplotlib tutorial for full examples.
Seaborn is built on Matplotlib, and makes statistical charts with less code and better default styling.
A notebook is not an IDE. It is a tool where you write code in cells and see the results, charts and notes right under each cell. It is a very popular way to learn and to share data work. An IDE, such as PyCharm, is a full development environment with a debugger and project tools.
No language is best at everything. This is a fair view of where Python stands.
| Python | Java | C++ | |
|---|---|---|---|
| Typing | Dynamic | Static | Static |
| Code length | Short | Longer | Longer |
| Speed for heavy work | Slower | Fast | Very fast |
| Learning curve | Gentle | Moderate | Steep |
| Best known for | Data, AI, scripting, web | Large business systems, Android | Games, systems, performance |
The newest release is Python 3.15, published on 9 October 2026. The python.org release page lists these highlights.
sentinel and frozendict.You do not need any of these to start. Learn the basics first. These are useful to know, because a beginner who installs the newest version will see them.
Here is the full script used to test every example on this page. Install the libraries first with the command below, and then run the script with Python 3.
Python is popular for a simple reason: you can start writing useful code on day one, and you do not outgrow it. Install it, run the first program from this page, and then change it. Add a loop, break it on purpose, and read the error. The language rewards curiosity. When you are ready, the next steps are variables and data types, then functions, then the libraries for the field you want to work in.