# Progress Milestones

Self-paced pathways work best when learners can periodically check their understanding.

These milestones are not evaluations or requirements. They simply help you confirm that your understanding is progressing as expected.

If you can confidently explain the concepts below, you are likely on track with the pathway.

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### Milestone 1 — Understanding Bitcoin’s Core Design

After completing Week 1, you should be able to explain:

* The double-spend problem
* Why Bitcoin uses a peer-to-peer network
* The difference between Bitcoin as a protocol and bitcoin as a currency
* How Bitcoin maintains a predictable monetary supply

> You should now understand why Bitcoin was designed the way it was.

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### Milestone 2 — Ownership and Cryptography

After completing Week 2, you should be able to explain:

* The role of Bitcoin Core in the ecosystem
* How public and private keys work
* How Bitcoin addresses are derived
* Why key management is fundamental to Bitcoin security

> You should now understand how ownership of bitcoin is defined cryptographically.

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### Milestone 3 — Transactions and Wallets

After completing Week 3, you should be able to explain:

* How Bitcoin transactions are structured
* The purpose of inputs and outputs
* How wallets track balances
* How wallet recovery works

> You should now understand how value actually moves across the Bitcoin network.

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### Milestone 4 — Authorization and Validation

After completing Week 4, you should be able to explain:

* How digital signatures prove ownership
* The role of Bitcoin Script
* How nodes verify that transactions are valid
* Why signatures cannot be forged

> You should now understand how Bitcoin ensures only the rightful owner can spend funds.

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### Milestone 5 — Network Operation

After completing Week 5, you should be able to explain:

* How transactions propagate through the network
* Why transaction fees exist
* How nodes communicate and maintain the mempool
* How miners choose which transactions to include in blocks

> You should now understand how Bitcoin operates as a decentralized network.

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### Milestone 6 — Consensus and Mining

After completing Week 6, you should be able to explain:

* How blocks are created
* How proof-of-work secures the network
* How nodes reach consensus
* Why forks and chain selection occur

> You should now understand how Bitcoin maintains a shared global ledger.

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### Milestone 7 — Security and Scaling 

After completing Week 7, you should be able to explain:

* Bitcoin’s primary security assumptions
* Major threat models to the network
* Why scaling directly on-chain is difficult
* How second-layer systems like Lightning extend Bitcoin

> You should now understand how Bitcoin continues evolving while preserving its core properties.

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### Completion Signal

If you can clearly explain how Bitcoin transactions are created, validated, propagated, and secured by the network, you have achieved the core objective of the Mastering Bitcoin pathway.

This foundational understanding prepares you to explore:

* Bitcoin development environments
* Bitcoin Core internals
* Open-source contribution pathways
* Advanced Bitcoin engineering topics