1 Web Services 1 Web services is one of the most exciting new developments in the field of computer  science,  and  also  one  of  the  most  misunderstood.  Some  people describe it as a technology designed strictly for publishing software services to the Internet, whereas others think of it as a general-purpose architecture that will trigger a fundamental shift in the way that all distributed systems are created. As youll see shortly, I definitely believe the latter. This chapter provides an introduction to web services that shows it is not a fad but a natural and logical evolution of distributed computing. It covers all of the important terms such as SOAP, WSDL, and UDDI, as well as touch- ing upon common questions related to performance and reliability. The chapter ends with a fun story that strongly influenced my interest in dis- tributed computing and offers a glimpse of where web services might lead. GLUE, my companys web services platform, is used for the first few chap- ters of this book because it is easy to learn, installs without hassle, and is free for most commercial uses. Later in the book I introduce some examples that use Microsoft .NET and J2EE, and show how these systems can interoperate using SOAP. If you want to follow along with the examples, now is a good time to read the appendix section titled Installing GLUE and the Examples. ch01.fm  Page 1  Friday, October 26, 2001  1:37 PM