Bitcoin is the first and most widely recognized cryptocurrency, designed to function as peer-to-peer electronic cash. It relies on the SHA-256 Proof-of-Work algorithm, where miners expend computational energy to secure the network and order transactions. This decentralized architecture ensures that the ledger is immutable and censorship-resistant, provided no single entity controls the majority of the mining power.

While Bitcoin’s base layer changes slowly by design, the ecosystem has seen significant innovation in asset issuance and programmability:

The 2024 Halving: In April 2024, the network successfully executed its fourth halving event. The issuance of new BTC per block dropped from 6.25 to 3.125, reducing the annual inflation rate to approximately 0.8%.

Runes Protocol (April 2024): Launched coincidentally with the halving, the Runes protocol introduced a standard for issuing fungible tokens on Bitcoin using the UTXO model. Unlike previous standards (like BRC-20), Runes are designed to be more efficient, reducing "blockchain bloat" while enabling a native token economy on Layer 1.

OP_CAT Discussions (2025): Throughout 2025, the developer community actively debated the re-introduction of OP_CAT, a deactivated opcode that could enable "covenants" and more complex smart contract functionality (like vaults and L2 bridges) directly on the Bitcoin network.

BTC serves three primary functions:

Store of Value: Often referred to as "digital gold," BTC is widely held as a long-term reserve asset due to its fixed supply schedule.

Medium of Exchange: BTC can be transferred globally without intermediaries, though transaction times and fees vary based on network congestion.

Network Fees: Users must pay miners in BTC to have their transactions (including Runes transfers and Ordinals inscriptions) included in a block.

Consensus: Proof-of-Work (SHA-256)

Max Supply: 21 Million BTC

Block Time: ~10 Minutes

Recent Upgrade: Runes Protocol (Token Standard)

Explore the Bitcoin Whitepaper: The Start of It All