Abstract
Web services are loose-coupled, which allows developers to create, generate and compose them at runtime. But, single Web service isn't sufficient to achieve most of user demand in the current period. Therefore, composition of Web services is the appropriate solution and it's the best way to deal with various user requests. It has received a great attention from different communities. A number of different standards/specifications have been proposed to tackle this issue. These standards are Ontology Web Language, Web Service Modeling Ontology, Business Process Modeling Language, Web Services Business Process Execution Language, Web Service Choreography Interface and Web Service - Choreography Description Language. In this paper, we provide an overview of different applications that have been developed based on each of these standards, and present three comparisons between those applications along with the popularity of Web search for them.