The Wireless AbominationApplication Protocol, an effort to bring the Web to mobile phones that has had nearly twice as much criticism as praise.

It is essentially a proxying mechanism that involves deploying a gateway between the WAP sites (HTTP servers with WML content) and the phone.

The phone issues WAP requests (typically UDP over GSM data or GPRS) to the gateway, which issues an HTTP request to the site, parses the WML and outputs a tokenized binary format to the phone.

As mobile phones increase their processing power and wireless bandwidth costs drop, WAP will (hopefully) become extinct, but in the meantime it's steadily (although not enthusiastically) progressing beyond version 2.0.