tDC microgrids (DC MGs) are characterized by attractive features such as high system efficiency, highpower quality, reduced cost, and less complex control. The hierarchical control is extensively proposedby researchers for DC MGs. This paper reviews and classifies different primary and secondary controltechniques applied to DC MGs. The load sharing mechanisms employed in primary control are distin-guished in passive methods and active methods. The different methods for secondary control are also categorized. Their key points and their limitations together with solutions that have been proposed by the research community are presented and