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Understanding Bitcoin

Bitcoin is a peer-to-peer electronic cash system described in a whitepaper published in 2008 by Satoshi Nakamoto. This guide explains how the blockchain works and how to explore it using Bitblocks.

What is a Block?

A block is a bundle of transactions confirmed by miners. Each block links to the previous one through a cryptographic hash, forming a chain.

Block 0
genesis
txs + hash
←
Block 1
txs + hash
←
Block 2
txs + hash
←
Block 3
latest →
txs + hash

Each block contains a hash of the previous block. Changing any block would break every block after it.

The very first block, called the genesis block, was mined on January 3, 2009. Every block since then traces back to it.

Explore blocks:

Browse blocks → | Visualize the first 10 blocks in 3D →

What is a Transaction?

A transaction transfers value from one or more inputs to one or more outputs. Each input spends a previous output, creating a chain of ownership called the UTXO set (Unspent Transaction Outputs).

The first transaction in every block is called the coinbase transaction. It creates new coins as a reward for the miner.

Explore transactions:

Browse transactions → | Trace a transaction's spending chain →

Locking and Unlocking Scripts

Every transaction output carries a locking script (ScriptPubKey) that defines who can spend it. The most common form is P2PKH — Pay to Public Key Hash — which requires the spender to provide a matching public key and a valid signature.

To spend an output, a transaction input must provide an unlocking script (ScriptSig) that satisfies the locking script. Together they form a small program that the network runs to verify the spend is authorized.

Some outputs use OP_RETURN — a special opcode that makes the output unspendable. These outputs carry data instead of value.

Example — a simple P2PKH payment (genesis block coinbase):

4a5e1e4baab89f3a32518a88c31bc87f618f76673e2cc77ab2127b7afdeda33b

Data on the Blockchain

Bitcoin SV transactions can store data in OP_RETURN outputs. This enables protocols like B:// (file storage), MAP (key-value data), and 1Sat Ordinals (inscriptions).

Bitblocks detects and parses these protocols, making on-chain data browseable.

Explore protocols:

Protocol Registry → | BSV Ecosystem in 3D →

Identity on Bitcoin

Decentralized Identifiers (DIDs) let you create a verifiable identity without a central authority. Bitblocks supports DID creation, Verifiable Credentials, and vCard-format profiles.

Try it:

DID Playground →

The Network

Bitcoin is a network of nodes that validate and relay transactions. Miners compete to add the next block to the chain. Bitblocks connects to a BSV node via RPC to sync and display blockchain data.

See the network:

Peer Map → | Network Pulse →

Further Reading