Complex sentence: In 2010 Oracle ended the development of OpenSolaris and ZFS as Open Source project, which led to the fork OpenZFS, an umbrella project aimed at bringing together individuals and companies that use the ZFS file system and work on its improvements.
Split into simpler sentences: In 2010 Oracle ended the development of OpenSolaris and ZFS as Open Source project, which lead to the fork OpenZFS. OpenZFS is an umbrella project aimed at bringing together individuals and companies that use the ZFS file system and work on its improvements.