This tutorial explains what WAP and WML are and how they can be used. (W3Schools)

Do you know what are WML, WMLScript, and WAP? Learn the basic terminology of the wireless world. (Doc JavaScript)

WAP homepages are not very different from HTML homepages. Get the basics here. (W3Schools)

Generally acknowledged as being the 'killer-app' of the Internet, e-mail is more frequently used than even the Web. As more and more people rush online, e-mail will become, even more, the ubiquitous means of communication between individuals, for all sorts of purposes, in many different spheres of activity.