This paper presents a comprehensive review of photovoltaic (PV) systems with more focus on PV inverters. At this stage, there is no consensus that this technology will play a major role or will be the first choice for energy generation in the future because of many reasons, the most important of which is its lack of efficiency. Different materials are used and other materials are expected to be used for developing PV cells, modules and power electronic devices in order to increase their efficiency and lifetime, and to reduce their costs. Future power electronic devices are expected to have reduced chip thickness, more specific converter topologies, better control of types of materials, improved nanotechnology, and inbuilt current bi-directionality. Different aspects will be discussed in this paper related to PV inverters including power electronic materials, topologies, grid codes, storage systems, and others.