SQLite

SQLite is a free and open-source relational database management system that implements a small, fast, self-contained, high-reliability, full-featured, SQL database engine. Rather than being a typical client–server database engine, SQLite is self-contained and can be embedded into applications. Making it perfect for development frameworks that want to provide a default database without setup, or applications that needs an embedded database. SQLite is built into all mobile operating systems and most computers and comes bundled with a countless applications. SQLite is also ACID-compliant and implements most of the SQL standard, generally following PostgreSQL syntax.