Asad's latest article shows us how easy Web Services can be employed using a combination of ingredients, including PHP and GD. Using an example Web Service, Asad shows us how to deploy our own. So, if you're interested in learning a little bit more about this so-called "phenomenon", be sure to have a read.
Cooking With Web Services: PHP & GD - Web Services (Page 2 of 5 )
In recent years, Web Services have become the most widely discussed and least understood technologies. Web Services represent a new model of software applications, with some very significant architectural differences that set them apart from earlier generations. Web Services are software components that are distributed and are programmatically accessible using standard Internet protocols. The big technological trio IBM, Microsoft, and Sun Microsystems have been investing tremendous efforts to develop specifications and security for Web Services.
There are basically two well-recognized platforms for Web Services. The first is J2EE, based on Java; the other based on the .Net framework. The two platforms are designed to provide the same functionality; the chart below shows the two platforms (similar in structure). However, Web Services can also be implemented and/or deployed using other technologies as well. For example, ColdFushion, AXIS, Delphi, GLUE, Apache SOAP and PHP NuSOAP are other various way of implementing Web Services.
Web Services 
Generating Images on the Fly With PHP
