Mobile Edge Computing (MEC) is a technology for mobile services. MEC integrates the cloud computing into the mobile environment and overcomes obstacles related to distance and the performance such as energy efficiency, storage, bandwidth, scalability and privacy in mobile computing. With the growing adoption of 5G technology, MEC offers a lot of technological and economic advantages to the developing economies amidst challenges associated with its implementation. This paper gives a survey of MEC, which helps every reader to have an overview of the concept and architecture of mobile edge computing. The challenges and prospects of its implementation in developing economies and the future research directions of MEC are presented.