JavaScript
JavaScript Functions and Arrow Syntax Explained
Function declarations, expressions and arrow functions — what the differences are, when each is right, and how callbacks fit in.
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JavaScript
JavaScript Variables: let, const and var Explained
Which keyword to use and why. Scope, hoisting, reassignment versus mutation, and why const objects can still be changed.
JavaScript
JavaScript for Beginners: How It Actually Works
What JavaScript is, where it runs, and the core syntax you need. Includes a first script you can run in your browser…
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…
Python
How to Install Python (and Check It Actually Worked)
Step-by-step Python installation for Windows, macOS and Linux, plus how to confirm it worked and fix the "python is not recognised" error.
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