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

# key concepts

- [Total Value Locked(TVL)](https://docs.zklink.io/key-concepts/total-value-locked-tvl.md)
- [Zero-Knowledge Rollup](https://docs.zklink.io/key-concepts/zero-knowledge-rollup.md)
- [zkEVM](https://docs.zklink.io/key-concepts/zkevm.md)
- [Layer 3](https://docs.zklink.io/key-concepts/layer-3.md)
- [Modular Blockchain](https://docs.zklink.io/key-concepts/modular-blockchain.md)
- [Token Merge](https://docs.zklink.io/key-concepts/token-merge.md)