An application consists of a program (perhaps with versions for different platforms) and a set of workunits and results. A project can operate many applications. Applications are maintained in the application table in the BOINC DB, and can be created using the xadd utility.

An application program may go through a sequence of versions. A particular version, compiled for a particular platform, is called an application version. An application version can consist of multiple files: for example, a controller script, pre- and post-processing programs, and a primary program.

Each application version has an integer version number. Version numbers should be used consistently across platforms; Windows version 304 should be computationally identical to Mac version 304.

Each application has a minimum version. When a client is sent work for an application, it is also sent the latest application version for its platform. It is sent work only if this version is the minimum or greater.

Application versions can be created using update_versions. Descriptions of application versions are stored in the app_version table in the BOINC DB. "; page_tail(); ?>