Sprint Nextel has made headlines all week as it’s started lighting up its first 4G wireless network using a technology called WiMax. But what exactly is WiMax? And how does it fit into the future of wireless? Here’s a primer to help you sort it out.Sprint was the first major carrier in the world to announce massive deployment of mobile WiMax in 2006. The company said it would use the technology to build a fourth-generation, or 4G, wireless network that would provide true wireless broadband.To read more of this CNET article, see news.cnet.com/8301-1035_3-10057282-94.html.