The Media Access Control (MAC) is an important layer of the Internet of Things (IoT). It is the lower sublayer of the data link layer. It allocates the communication resources effectively for device interconnectivity and provides reliable communication. Moreover, it can coordinate different IoT devices during data transmission. Numerous MAC protocols are designed for IoT to meet the challenges like restricted resources, minimum delay, and collision avoidance. The IoT necessitates energy-efficient MAC protocols to handle the issues associated with tiny resource-constrained IoT devices. Sleep schedule is the familiar model utilized in MAC protocol design in which the energy consumption issues are handled perfectly. The main design consideration of MAC protocols in IoT is throughput, energy efficiency, low latency, scalability, and mobility. The IEEE 802.11, sensor S-MAC, timeout T-MAC, DSMAC, WiseMAC, TRAMA, and DMAC are MAC protocols exploited for IoT. Albeit several standards developed for the MAC layer in IoT, it is essential to design scalable MAC protocols to ensure concurrent, dynamic, and massive media access control.