Web Services and Loose Coupling

As you have learned, a web service contains code that programs can call from across the Internet to perform a specific operation. The term “coupling” describes the degree of dependence between a calling program and the web service. Ideally, to use a web service, a program need only know the location of the web service (its URL), the name of the functions (methods) the web service provides, and parameters the program can pass to the functions. In this way, programs and web services are said to be loosely coupled.

Because of a program’s loosely coupled relationship to a web service, it is possible for a developer to update a web service with a newer version (perhaps a faster version) and for programs that use the service to immediately put the new version to use without requiring any modifications.