HazelCast --> what is hazel cast?

Today I looked at HazelCast and wrote some code using the library. I found this library to be extremely useful and simple. Some of the advantages found in hazelcast are,

1. It can be used as a No-SQL data store - http://www.hazelcast.org/use-cases/in-memory-nosql/
2. Useful for messaging (pub/sub, topics etc...) - http://www.hazelcast.org/use-cases/messaging/
3. Can be used as a data-grid - http://www.hazelcast.org/use-cases/data-grid/
4. Can be used for caching - http://www.hazelcast.org/use-cases/caching/
5. For application scaling - http://www.hazelcast.org/use-cases/application-scaling/
6. For clustering sessions in java web apps - http://www.hazelcast.org/use-cases/clustering/