The facade pattern is a wrapper of many other interfaces in a result to produce a simpler interface.
Design patterns are useful as they solve recurring problems and in general simplify code. In a team of developers who agree to use the same patterns it improves efficiency and understanding when maintaining each others code.
Try reading about more patterns:
Facade Pattern: http://www.dofactory.com/Patterns/PatternFacade.aspx#_self1
or more generally: http://www.dofactory.com/Patterns/Patterns.aspx