In the world of enterprise computing, communication between different servers has typically been used for data interchange so that clients can request services offered by third-party servers. With the mobile revolution, this transferring of information between computers and making remote requests for information has become common in the mobile world as well.

Consider the simple weather application on your mobile device. Typically, this will obtain its location as a latitude and longitude and will then invoke a remote server to obtain the weather information before displaying it to you. There's no way that your mobile device can forecast the weather for your current location, let alone for where you're vacationing next week. This is where web services come into play.

Originally, data interchange between client and server used proprietary technologies such as Common Object Request Broker Architecture (CORBA) or Remote Method Invocation (RMI). These...