About 71% of earth is covered with water and yet it is ironical that one most the most dangerous problem the world is facing now is water scarcity. About 97% of available water is in the form of ocean so it is not potable. Conventional desalination processes involve use of either coal or electricity, but as climate change is becoming a serious problem with each passing day more research needs to be done in using non-conventional sources for heating water like solar or wind energy. This paper is a review of various design parameters and climatic conditions that affect the output of a solar still. It also deals with the effects of use of carbon nano particles and PCM (Phase Change Materials) on the output of a solar still.