The Adapter pattern is a structural pattern that allows two objects with incompatible interfaces to interact. Adapter pattern is also known as a wrapper.
UML Diagram Example
RoundHole that has a function called fits() that takes in a RoundPeg object and returns if it fits. We also have a SquarePeg class that creates incompatible objects, lucky we have our SquarePegAdapter class that implements the roundPeg and that takes in a a SquarePeg object and making it compatible with RoundHole class
Chris's Blog 