Vehicular Ad-hoc Network (VANET) is a new emerging wireless technology concept that supports communication amongst various nearby vehicles themselves and enables vehicles to have access to the Internet. This networking technology provides vehicles with endless possibilities of applications, including safety, convenience, and entertainment. Examples of these applications are safety messaging exchange, real-time traffic information sharing, route condition updates, besides a general purpose Internet access. The goal of vehicular networks is to provide an efficient, safe, and convenient environment for vehicles on the road. In this paper some wireless access standards for Vehicular Ad hoc Network (VANET) and describe was present, this paper starts with the basic architecture of networks, then discusses some of the recent VANET trials, also briefly present some of the simulators currently available to VANET researchers. Finally, discusses the popular research issues and general research methods, and ends up with the analysis of challenges and future trends of VANETs.