# After installing

This section provides reference information about the installation directory, JVMs, classpath, upgrades, and platform-specific issues.

Review the `index.html` file at the top level of the Derby distribution for pointers to reference and tutorial information about Derby. See the Release Notes for information on platform support, changes that may affect your existing applications, defect information, and recent documentation updates. See Getting Started with Java DB for basic product descriptions, information on getting started, and directions for setting the path and the classpath.

- The installation directory
  You may install the Derby software in a directory of your choice.
- Derby and JVMs
  Derby is a database engine written completely in Java; it will run in any JVM, version 1.4 or higher.
- Derby libraries and classpath
  Derby libraries are located in the /lib subdirectory of the Derby base directory. You must set the classpath on your development machine to include the appropriate libraries.
- UNIX-specific issues
  This section discusses Derby issues specifically related to UNIX platforms.