> For the complete documentation index, see [llms.txt](https://docs.zkbridge.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.zkbridge.com/zkbridge-trustless-cross-chain-bridges-made-practical.md).

# zkBridge: Trustless Cross-chain Bridges Made Practical

- [Introducing zkBridge protocol](https://docs.zkbridge.com/zkbridge-trustless-cross-chain-bridges-made-practical/introducing-zkbridge-protocol.md)
- [Block header relay network](https://docs.zkbridge.com/zkbridge-trustless-cross-chain-bridges-made-practical/block-header-relay-network.md)
- [Updater contract](https://docs.zkbridge.com/zkbridge-trustless-cross-chain-bridges-made-practical/updater-contract.md)
- [Proof systems of zkBridge](https://docs.zkbridge.com/zkbridge-trustless-cross-chain-bridges-made-practical/proof-systems-of-zkbridge.md)
- [zkBridge Research Paper](https://docs.zkbridge.com/zkbridge-trustless-cross-chain-bridges-made-practical/zkbridge-research-paper.md)