Ultra-wideband (UWB) communications is a new field of technology that has a wide range of applications from range finding to wide bandwidth communications. Ultra-wideband signals are unusual because their bandwidth to center frequency ratio is not small and can be greater than 100%. Recent developments of integrating this technology on a chip have made it versatile and low cost. This technology also offers some special features like interference immunity, multi-access communications, and accurate range finding. A number of areas which need cooperative communications can benefit from this technology including automated highway systems (AHS) and military systems. This paper describes the basics of UWB technology, provides background on the technology, and provides some possible applications of UWB.