This paper presents an overview of the most recent advances in DC distribution systems. Due to the significantly increasing interest that DC power systems have been gaining lately, researchers investigated several issues that need to be considered during this transition interval from current conventional power systems into modern smart grids involving DC microgrids. The efforts of these researchers were mostly directed toward studying the feasibility of implementing DC distribution on a given application, DC distribution design-related aspects such as the system architecture or its voltage level, or the unique challenges associated with DC power systems protection and stability. In this paper, these research efforts were categorized, discussed and analyzed to evaluate where we currently stand on the migration path from the overwhelming fully AC power system to a more flexible hybrid AC/DC power system. Moreover, the impediments against more deployment of DC distribution systems and some of the proposed solutions to overcome those impediments in the literature will be discussed. One of the obstacles to increased DC system penetration is the lack of standards. This problem will be discussed, and the most recent standardization efforts will also be summarized and presented.