SQLite is an embedded SQL database engine: a C-language library that is built into an application and keeps data in tables that the application queries with SQL (Structured Query Language). An international team of developers works on it full-time; the project started in May 2000.
Unlike most SQL databases, SQLite has no separate server process. The application calls the library, and the library reads and writes ordinary disk files directly. A complete database, with its tables, indexes, triggers and views, is one file, and that file can be copied between 32-bit and 64-bit systems and between processors with different byte orders. SQLite needs no setup or configuration. Its transactions are ACID (atomic, consistent, isolated and durable: a change is either completed fully or not at all), even after a system crash or a power failure. With all features enabled, the library can be smaller than 900 KiB, and one database can hold up to 281 terabytes.
The source code of SQLite is in the public domain, so anyone may use it for any purpose, commercial or private, at no cost. Professional support is also offered.