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Free module

Blockchain and distributed ledgers

Learn how a blockchain works hands on: hash chains, proof of work, ledgers, signatures, forks and when not to use one.

6 lessons365 min lessonSoftware engineering

The lessons

Each lesson is free to read in full. Create a free account to run its commands in a live lab and to sit its quizzes and tasks.

  1. 1 · Container lab

    How a hash chain works

    I can link blocks with hashes so that a change to an old block is detectable.

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  2. 2 · Container lab

    How proof of work and mining work

    I can explain why mining a block costs work while checking it is cheap.

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  3. 3 · Container lab

    How a ledger stops double spending

    I can work out balances from a list of transactions and refuse an overspend.

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  4. 4 · Container lab

    How a digital signature shows who paid

    I can explain how a signature shows who sent a payment and that it was not changed.

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  5. 5 · Container lab

    How a blockchain chooses between forks

    I can choose the valid chain with the most work from several chains.

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  6. 6 · Container lab

    When not to use a blockchain

    I can say when a blockchain is the wrong tool and name a simpler one.

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Worked in a real lab

Every lesson of this module is worked in a lab started for you alone. The labs it uses:

Teaching a class? Set this module for your students with a teacher guide, marked assignments and a lab for every student.