An adapter, by definition, helps the interfacing or integrating components adapt. In software it represents a coding discipline that helps two different modules or systems to communicate with each other and helps the consuming side adapt to any incompatibility of the invoked interface work together.

Incompatibility could be in the form of input data elements which the consumer does not have and hence might require defaulting or the invoked interface might be a third party interface with a different message format requiring message translation. Such functions, which do not form part of the consumer functionality, can be implemented in the adapter layer.