PlanetScale is a database platform that provides a scalable, developer-friendly solution for managing MySQL databases in the cloud. It is built on the open-source Vitess project, which has been proven to handle massive scale and high query throughput. PlanetScale offers features such as non-blocking schema changes, horizontal scaling, branching, and sharding, enabling users to develop flexibly without downtime. The platform emphasizes simplicity and performance, making it suitable for modern applications that require a robust and efficient database infrastructure.