Python
Python Virtual Environments Explained
A virtual environment is a private folder of packages for one project. Why you need one, how to create and activate it…
Python
Plain-English Python guides, from installing it to writing small programs that do real work. Short examples you can copy, run and change.
14 guides
Python
Reading and Writing Files in Python
How to open, read, write and append files in Python using with, plus the path and encoding traps that make files behave…
Python
Python try / except Explained
How to handle errors instead of crashing: catching specific exceptions, else and finally, raising your own, and why a bare except will…
Python
Python While Loops Explained
A while loop repeats for as long as a condition stays true. How to write one, when to use it instead of…
Python
Python Functions Explained
Defining functions, parameters and defaults, keyword arguments, return values, scope, docstrings and when to split code into functions.
Python
Python Dictionaries Explained
Dictionaries store labelled values. Here is how to create, read, update and loop over them, plus how to avoid the KeyError that…
Python
Python Lists Explained
Creating lists, indexing, slicing, adding and removing items, sorting, and the copy trap that catches every Python beginner at least once.
Python
Python For Loops Explained
How for loops work in Python: looping over lists, using range, enumerate and zip, break and continue, and building a list from…
Python
Python If, Elif and Else Statements
How conditions work in Python: comparison operators, elif chains, and, or, not, truthiness, and why indentation decides what runs.
Python
Python Data Types Explained
Strings, integers, floats, booleans, lists, dictionaries and None — what each is for, how to convert between them, and how to check…
Python
Python Variables Explained
How variables work in Python: creating them, naming rules, multiple assignment, and the mutable-versus-immutable behaviour that surprises beginners.
Python
Your First Python Program (Line by Line)
Write, save and run your first Python program, then extend it. Every line explained, plus the three errors beginners hit in the…
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The ideas every language shares — variables, loops, functions and how a program actually runs.
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How JavaScript works in the browser, explained with short examples you can paste and run.
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Web Development
HTML, CSS and the pieces that turn code into a page people can visit.
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The fastest way to improve is to read one guide, then build the thing it describes. Start with the basics, or jump straight to a project.