Most mowers take the same kind of gas you put in your car. There are electric mowers, which operate with a plug instead of gas. Mixed gas is only used for engines that power chainsaws, edge and hedge trimmers, and similar tools that need to combine oil and gas together. Depending on what kind of mower you purchase it is always good to read the operating instructions. These instructions will tell you what kind of gas to use, how to winterize the engine and how often you should sharpen the blades.