> For the complete documentation index, see [llms.txt](https://hub.bsvblockchain.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://hub.bsvblockchain.org/higher-learning/bsv-academy/bitcoin-script-new/introduction-to-bitcoin-script.md). # Introduction to Bitcoin Script Every time a Bitcoin transaction is broadcast to the network, a program runs. That program is **Bitcoin Script**— a compact, elegant scripting language that defines the rules for spending coins. Unlike traditional bank transfers that simply move numbers between accounts, Bitcoin uses Script to encode the **conditions** under which value can move. This means Bitcoin is programmable at its most fundamental level. This course takes you inside that system. You will trace Bitcoin Script's ancestry back to **FORTH**, a 1970s stack-based language that pioneered many of the ideas Satoshi Nakamoto would later use in Bitcoin. You will then dissect the structure of a Bitcoin transaction field by field, learning how **locking scripts** (scriptPubKey) and **unlocking scripts** (scriptSig) work together in a script evaluator to authorize value transfer. By the end, you will have the conceptual tools to read, understand, and reason about Bitcoin transactions at the protocol level. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://hub.bsvblockchain.org/higher-learning/bsv-academy/bitcoin-script-new/introduction-to-bitcoin-script.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.