Introduction to Computational Thinking
A serverless republish of MIT's Computational Thinking (18.S191) — by Alan Edelman, David P. Sanders & Charles E. Leiserson.
The original course makes its notebooks interactive with a live PlutoSliderServer backend. Here, every notebook is compiled to WebAssembly and runs right in your browser — no server, no kernel, no install — hosted free by Snapshot.
The full course is three modules · 24 interactive lessons. The sidebar groups every lesson under its module — open any one, drag its sliders, and every figure recomputes live.
Module 1 · Images, Transformations & Abstractions
Images as Data and Arrays — a picture is just a grid of numbers you can slice and edit.
Abstraction — one operation, any type: the heart of computational thinking.
Automatic Differentiation — exact derivatives from dual numbers, built from scratch.
Transformations with Images — convolution filters: blur, sharpen, find edges.
Transformations II — a 2×2 matrix is a linear map; drag it and watch a grid bend.
The Newton Method — follow the tangent to a root and watch it converge.
Dynamic Programming — find the cheapest path down a grid of costs in one sweep.
Seam Carving — content-aware image resizing, powered by that same dynamic program.
Taking Advantage of Structure — diagonal, sparse and low-rank: store less, compute more.
Module 2 · Social Science & Data Science
Random Walks — a coin flip each step; watch tiny noise add up into √t spreading.
Epidemic Modeling (SIR) — three coupled rates turn a handful of cases into a wave.
Estimating π with Random Darts — throw darts at a square, count the circle, recover π.
Optimization by Gradient Descent — roll downhill on a landscape to find its lowest point.
Random Variables & the Bell Curve — add many small randoms and the normal curve appears.
Random Walks in 2D — the same drunkard's walk, now wandering across a plane.
Fitting a Line (Least Squares) — the single line that sits closest to a cloud of points.
Principal Component Analysis — find the direction your data actually varies along.
Reliability — exponential lifetimes and the odds a system is still running.
Module 3 · Climate Science
The Energy Balance Model — sun in, heat out: the one equation that sets Earth's temperature.
The Greenhouse Effect — how CO₂ traps outgoing heat and shifts the balance.
Feedbacks & Climate Sensitivity — ice and water vapor amplify a small push into a big one.
Snowball Earth & Tipping Points — when feedbacks run away and the planet flips state.
Heat Diffusion in the Ocean — heat spreading down through depth, a 1-D PDE solved by hand.
Carbon Emissions & Future Warming — turn an emissions path into a projected temperature curve.
Pick any lesson from the sidebar to begin — drag the sliders and everything recomputes live in your browser, no installs and no account.
Course material © the original authors — code under MIT, text under CC BY-SA 4.0. This is an unofficial educational republish.