> For the complete documentation index, see [llms.txt](https://docs.endur.fi/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.endur.fi/docs/concepts.md).

# Concepts

- [What is xSTRK?](https://docs.endur.fi/docs/concepts/what-is-xstrk.md)
- [What is xstrkBTC?](https://docs.endur.fi/docs/concepts/what-is-xstrkbtc.md)
- [What are BTC LSTs?](https://docs.endur.fi/docs/concepts/what-are-btc-lsts.md)
- [LST Architecture](https://docs.endur.fi/docs/concepts/lst-architecture.md)
- [Deposit - Withdraw matching](https://docs.endur.fi/docs/concepts/deposit-withdraw-matching.md)
- [Withdraw log](https://docs.endur.fi/docs/concepts/withdraw-log.md)
- [Relayer](https://docs.endur.fi/docs/concepts/relayer.md)
- [Community](https://docs.endur.fi/docs/concepts/community.md)