Wireless computer networks have been around for a long time. Most have been based on radio wave technology, but some have used optical or infrared beams instead.
One of the earliest successful implementations, in place as early as 1970, was the "Aloha" network at the University of Hawaii. It used conventional radio-frequency transmitters and receivers to span distances between cities and Islands in Hawaii.
Of course, in order for computers to participate in any network, they must all agree on the precise meaning of the signals they exchange. Every detail of the radio or infrared beams that they exchange must be defined so that they can be translated into meaningful, unambiguous bits and bytes.
When groups of people get together to seek agreement on these details, they produce "Protocol Documents" that serve as guidelines for others. The most successful protocols are generally sponsored by influential trade associations or governments.
Since the early days of the "Aloha" network, the Wireless Networking industry has seen the rise of several protocols that have become popular, and as the science of computer networking has evolved, the most important and popular protocols have coalesced into a rich group of technologies that can interoperate with one another to varying degrees. These are generally known as the "WiFi" protocols.
