Abstract
The use of Web services as a standard technology facilitates seamless business-to-business (B2B) interaction and the process of integrating various systems and applications. It enables mass knowledge distribution by providing a standard way of exposing data sources and applications/systems as Web services. These services can be created/generated, updated, and composed at runtime because they are loosely coupled. Web service composition provides the ability to compose services by manually or automatically generating a service composition plan in order to achieve the business goal, resolve a scientific issue/problem or provide new service functionality. They are reusable services that can be used to implement a business process. Web service composition can be achieved via two models: dynamic and static. This paper introduces taxonomy of Web service composition models and approaches, and provides a survey of Web service composition models and their approaches. Additionally, we present comparisons of different models and approaches for each model.