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Code Quest

A free school of computing · ages 7 to expert

Computers are not magic.
Open one and see.

Flip a switch, build a logic gate, watch electrons open a transistor, single-step a processor. Every lesson shows you what really happens inside the machine, then lets you try it.

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Fig. 0A processor at work. Every glowing dot is a 1 travelling down a wire; a real chip moves billions of them each second.

26

lessons

28

simulations

3

languages

Experiment 01

Make a prediction first

A transistor is a switch with no moving parts, and your phone has billions of them. What actually turns one on?

How every lesson works

People learn far more from an experiment when they predict the result first. So every lesson follows the same four beats.

  1. 01

    Predict

    Commit to a guess before you see anything. A wrong guess is where real learning starts.

  2. 02

    Experiment

    Run the simulation. Flip one bit, change one line, and watch every wire and register respond.

  3. 03

    Explain

    See the idea underneath, one layer of the machine at a time, in plain words.

  4. 04

    Remember

    Key ideas become flashcards that come back right before you would forget them.

Climb from one bit to sixty-four

Five stages. Start with a single switch that is on or off. Finish understanding processors, compilers and the limits of computation.

011-bitSparksAges 7–10 · first stepsOn and off, pictures made of switches, and giving a robot exact instructions.Inside the MachineGiving Instructions024-bitBuildersAges 10–13Counting in binary, letters as numbers, logic gates and a circuit that adds.The Secret Code of ComputersLogic: Machines that Decide038-bitCodersAges 13–16How a transistor works, gates made of transistors, memory, and your first real programs.The Transistor: the Switch that Changed EverythingYour First Programs0432-bitEngineersAges 16–18Inside the processor, machine code, compilers, searching, sorting and big O.How a CPU WorksFrom Code to MachineAlgorithms: Thinking Fast0564-bitArchitectsAges 18+ · advancedTuring machines, the limits of chips, the call stack and floating-point numbers.The Limits of ComputationHow Programs Really Run
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A lab where nothing breaks

Open a transistor in 3D, wire up an adder, run a tiny computer one clock tick at a time, race sorting algorithms. Every simulation is one click away.

⚛️Inside a transistorTransistors and chips🧠A tiny computerInside the processor🚦Logic gatesLogic and circuits🤖Program the robotPrograms and languages🪜From code to electronsInside the processor📊Sorting raceAlgorithms📼Turing machineTheory of computation⏳180 years of codingHistory of computing
Enter the Lab

Computing has a story

From al-Khwarizmi's algorithms and Ada Lovelace's first program to the transistor, the web and today's AI: meet the people who built it.

📖Muhammad ibn Musa al-Khwarizmic. 780 – c. 850🐘Ismail al-Jazari1136 – 1206🪶Ada Lovelace1815 – 1852🧠George Boole1815 – 1864🍏Alan Turing1912 – 1954📡Claude Shannon1916 – 2001⚓Grace Hopper1906 – 1992🏛️John von Neumann1903 – 1957🌙Margaret Hamiltonborn 1936🛠️Dennis Ritchie and Ken Thompson1969 – 1973🕸️Tim Berners-Leeborn 1955🐧Linus Torvaldsborn 1969
Read the history

Your first experiment takes two minutes

Pick your stage and flip your first switch now. Create a free account whenever you want your progress saved.

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