It's really quite a simple pattern to grasp and to implement. A Facade provides a simple API that shields its user from the complexities of a more fine grained API, or set of APIs, which are more difficult to use. The advantage is ease of use, because the Facade's API is coarse grained. That is, however, also the main drawback: loss of flexibility / fine grained control over the shielded API(s). Code samples are easy to find using good ol'Google, but the Wikipedia entry does an okay job.
Build a man a fire, and he'll be warm for a day. Set a man on fire, and he'll be warm for the rest of his life.