Edge computing, defined by different entities as computing outside the cloud for real-time data processing, a networking philosophy bringing computing close to data sources, and a distributed platform integrating networking, computing, storage, and applications at the network edge, is a distributed paradigm that processes data near sources or end devices. Compared with cloud computing, it features shorter physical distance, distributed computation mode, lower response latency, less network usage, higher cost efficiency, and stronger privacy protection. Three key edge computing paradigms are detailed, including fog computing, multi-access edge computing, and end-edge-cloud computing.