Bitcoin Script
Bitcoin is commonly thought of as a cryptocurrency, and whether or not that's technically accurate, it was designed to be electronic cash; as described on the first sentence of the BitCoin whitepaper.
Bitcoin's scripting language is a stack-based language, very similar to Forth. And, over time, functions will be written and re-used onchain.
Thus far, the scripting language has proven to be difficult to adopt, test, and use, and other tools (and chains) have made more progress with on chain scripts.
Scrypt is a tool focused on BitcoinSV (BSV) that compiles/transpiles Typescript code to bitcoin script, made of OP_CODES.