Oil, grease, asphalt, tar and road dirt place different demands on cleaning, making the choice of degreaser important for effective results. Cold degreasers are degreasers based on petroleum feedstocks. Alkaline degreasers are based on water, various surfactants and alcohols to create a product that tackles many types of dirt. Micro-degreasers combine cold degreasers and alkaline degreasers.