Simple Object Oriented Protocol or SOAP is a simple, light weight, XML based protocol that can be used for exchange of data in a de-centralized, distributed environment.  It is making headlines these days within the enterprise development community and promises to revolutionize Web applications development by facilitating interoperability between heterogeneous applications.  Using the SOAP protocol, objects of any kind, developed on any platform, using any language can cross communicate with each other.  Hence, we can connect the services offered by different heterogeneous systems together as components and use these components to build a complex information system with ease.  This article provides a detailed overview of SOAP in a lucid language.