> For the complete documentation index, see [llms.txt](https://docs.bsquared.network/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.bsquared.network/technical-design/da_layer/bitcoin.md).

# Bitcoin Network

Bitcoin serves as the ultimate settlement layer for B² Network. B² rollup data is stored on Bitcoin, allowing complete retrieval or restoration of B² rollup transactions based on the B² inscriptions on Bitcoin. The computational validity of zk proof verification of rollup is confirmed on Bitcoin, thereby confirming the B² rollup.