# Introduction to Derby

Welcome to Derby! Derby is a full-featured, open source relational database management system (RDBMS) that is based on Java technology and SQL.

Derby is written and implemented completely in the Java programming language. Derby provides users with a small-footprint standards-based database engine that can be tightly embedded into any Java based solution. Derby ensures data integrity and provides sophisticated transaction support. In the default configuration there is no separate database server to be installed or maintained by the end user. For more information on Derby, visit the Derby Web site at http://db.apache.org/derby.

The on-disk database format used by Derby is portable and platform-independent. You can move Derby databases from machine to machine without needing to modify the data. A Derby application can include a pre-built, populated database if it needs to, and that database will work in any Derby configuration.

Before you install Derby, you should understand the deployment options and system requirements.

- Deployment options
  The Derby software distribution provides two basic deployment options (also referred to as frameworks), the simple embedded option and the Derby Network Server option.
- System requirements
  Derby is a database engine written completely in the Java programming language. The database will run in any certified Java Virtual Machine (JVM).
- Product documentation for Java DB
  The Java DB product documentation consists of the Java DB manuals and the API reference.