Today, with the need of connecting information anytime, anywhere, especially mobile Internet and Internet of Things (IoT), this has set three important requirements:solving the number of connections, increasing the speed of access and higher security than current networks. The ITU-R team has developed contents that related to the technical specifications of the 5th generation (5G) mobile communication system called IMT-2020. In order to address one of the three major requirements of network operators, which is high availability connectivity, non-orthogonal multiple access technologies (NOMA) have been used to solve the problem. In contrast to orthogonal multi-access technology, NOMA serves a large number of users due to the non-orthogonal resource allocation. This article will introduce NOMA techniques and standards for peak data rates, user experience, bandwidth, reliability, latency, transmission capacity. . .