— Vehicular networking has significant potential to enable diverse applications associated with traffic safety, traffic efficiency and infotainment. In this survey and tutorial paper we introduce the basic characteristics of vehicular networks, provide an overview of applications and associated requirements, along with challenges and their proposed solutions. In addition, we provide an overview of the current and past major ITS programs and projects in USA, Japan and Europe. Moreover, vehicular networking architectures and protocol suites employed in such programs and projects in USA, Japan and Europe are discussed. Keywords-; Vehicular networking, V2V, V2I, SAE, IEEE 802.11p, WAVE, IEEE 1609, ISO CALM, ARIB, IntelliDrive, VII, SEVECOM, VSC, SAFESPOT, CVIS, SMARTWAY, ASV, ITSSafety 2010, eSafety, COMeSafety