Bitcoin Runes, a protocol that enables the creation and transfer of fungible tokens on the Bitcoin blockchain, was launched by developer Casey Rodarmor on April 20, 2024. Unlike Ethereum and Solana, Bitcoin's scripting capabilities are limited, but Bitcoin Runes leverages these limitations to introduce features previously thought unfeasible.

The protocol employs Bitcoin's UTXO architecture and the OP_RETURN opcode, minimizing the data load on the Bitcoin blockchain. Each UTXO can contain varying amounts or types of Runes, streamlining token management. The OP_RETURN opcode allows extra information to be attached to Bitcoin transactions, storing key token data such as the token's name and ID.

Creating a Bitcoin Rune, or "etching," sets its properties immutably on the Bitcoin blockchain. These properties cannot be altered once set, even by the token's creator. Users can then "mint" the rune according to the parameters specified in the rune, similar to participating in a token sale.

However, the Bitcoin Runes protocol is not without its limitations. The naming system, which only allows letters from A-Z and uses the • symbol for spacing, has resulted in seemingly strange names. Furthermore, while the protocol adds new functionality to the Bitcoin blockchain, its primary use so far has been to mint meme tokens. This limited application, coupled with the protocol's complex nature, may hinder its widespread adoption.