This document provides an overview and summary of TiDB, an open-source distributed SQL database compatible with MySQL. It discusses TiDB's architecture which includes TiDB for the SQL layer, TiKV for storage, and PD for placement driving. TiDB provides features like horizontal scalability, distributed transactions, and high availability. Example use cases are also presented, like Mobike's use of TiDB for locking/unlocking bikes and real-time analytics of bike usage data across 200 cities in China.