The residue of crude oils use to prepara candle, petrolium jelly such as vaseline, many petro chemicals such as styrene, benzene, naptha etc .petrolium jellies are use as screen cream .it is use to reduce the dryness of screen.candles are used as light.styrene is used to prepare polystyrene.bezene is used as solvent to prepare many organic compounds.Besides this glycerine, glycol etc are prepared from petrolium residue.Hence all the parts of petroleum are very useful for us.