GemFire allows users to share application data across multiple Java Virtual Machine using familiar Java classes and programming constructs.
GemFire's distributed caching allows application access to distributed and cached data across multiple physical machines. GemFire's main API for accessing distributed data is the {@linkplain org.apache.geode.cache.Region}
GemFire provides a flexible and powerful API for distributed object caching. The API is particularly well-suited for caching application data and contains classes for receiving data events, reading and writing data to and from external sources, querying cached data using OQL, performing transactional operations, and active monitoring of data and data VMs.
A discussion of the Distributed Caching API and GemFire's implementation of it can be found {@linkplain org.apache.geode.cache here}.