Mathematics
The language reality is written in - sets, numbers, probability, and more - taught from intuition, for anyone who was told they're 'bad at math'.
Basic
Why Math Isn't Your Enemy If you think you're 'bad at math,' you were taught it wrong - not built wrong. This guide reframes what math is, decodes the scary notation, and hands you the mindset that finally makes it click.
Numbers & Number Systems Numbers come in expanding families - counting numbers, integers, fractions, the reals - each invented to fix something the last couldn't do. And the same number can be written in different bases, which is the whole reason computers think in binary and hex.
How to Think Like a Mathematician Problem-solving as a learnable craft: Polya's four steps, trying small cases, finding invariants, and getting unstuck when you are stuck.
Intermediate
Sets, Relations & Functions The three ideas almost all of math (and a lot of code) is built from: a set is a collection of distinct things, a relation connects things, and a function maps each input to exactly one output. Learn these and the rest of math has a vocabulary.
Counting & Combinatorics How to count possibilities without listing them: multiply independent choices, and know when order matters (permutations) versus when it doesn't (combinations). It's the math behind probability, password strength, and why brute force blows up.
Probability & Statistics Probability measures how likely something is; statistics makes sense of data once it's collected. Together they're the everyday superpower for reasoning under uncertainty - and the single best defense against being fooled by numbers.
Number Theory: The Secret Life of Integers Number theory is the math of which numbers behave nicely - and it is the reason your credit card number can travel over the internet without being stolen. This guide starts from prime fingerprints and builds up to the clock math that secures your browser.
Trigonometry: The Math of Circles and Waves Trigonometry is not 'memorize SOH CAH TOA.' It is the math of anything that repeats: sound waves, seasons, rotations, heartbeats. This guide starts from a point moving around a circle and builds up to the sine, cosine, and tangent that power graphics, audio, and animation.
Advanced
Linear Algebra: The Math of What Happens If I Change This? Linear algebra is the math of transformation: what happens when you stretch, rotate, or combine things. Every photo filter, 3D game, and machine learning model is built from it. This guide starts from real movement and builds up to matrices without the terror.
Calculus: The Math of How Things Change Calculus is not about memorizing derivative rules. It is the math of change: how fast something is moving, how to find the best possible outcome, how to add up a million tiny pieces. This guide starts from a car's speedometer and builds up to the ideas behind machine learning gradients and physics simulations.