What is a Hybrid Cloud?
 
One example is to have one or more in-house servers that work in tandem with one or more virtual servers in the cloud.
 
The benefits in brief is to provide a redundant, access to all systems that reaps the benefits of both Cloud and in-house servers.
 
A simple example would be a single in-house server that is based at head office for a company that has multiple remote sites.  The in-house server and the Cloud server mimic each other in terms of the data and services they provide.  They are link together via the internet.   The workers at head office will get a nice fast reliable connection to their in-house server while the remote sites have access to the Cloud server viewing the same data simultaneously.
 
If for whatever reason the internet connection, in-house server or cloud server goes down, Workers from either the remote sites or head office will still be able to function.  When the issue is resolved the servers simple sync back any changes to each other.  Thus providing a powerful redundant system.