Vehicular Ad hoc Network (VANETs) help improve efficiency of security applications and road safety. Using the information exchanged between vehicles, the latter can warn drivers about dangerous situations. Detection and warning about such situations require reliable communication between vehicles. In fact, the IEEE 802.11p (WAVE: Wireless Access in the Vehicular Environment) was proposed to support the rapid exchange of data between the vehicles. Several Medium Access Control (MAC) protocols were also introduced for safety application VANET. In this paper, we present the different MAC basic protocols in VANET. We used simulation to compare and analyze their performances.