(1) A value that identifies the interfaces supported by a service program. Signatures are based on the exports and the sequence of the exports allowed from a service program.
(2) The collection of types associated with a method. The signature includes the type of the return value, if any, as well as the number, order, and type of each of the method's arguments.
(3) The set of unique information that identifies a software application, such as the name, version, and file size of an application.
(4) The name and parameters of a behavioral feature.