A Web Service is a self-contained application that performs certain functions that you can publish on the Web based on open standards. A Web Service facilitates communication between applications because it is not platform-specific or language-based.

A Web Service functions like a black box, because you can provide input and expect certain output without knowing exactly how the results are achieved. Since Web Services are platform-neutral and comply with open standards, more businesses can interact with one another through integration of applications, even those written in different languages. For example, Windows applications can talk to UNIX applications, and Java can talk to Perl.

Most companies develop software for their specific business functions. However, due to increased associations among businesses, and international commercial collaboration, companies need a way to share information stored in separate computer systems. A Web Service makes it possible for applications within computer systems to communicate with each other.

Through a Web Service, business logic, processes, and data can be reused by different applications. This significantly reduces the amount of time it takes to develop applications by eliminating the need to replicate business functions.