No one likes getting dirty. And I don’t just mean on the outside. Slick, wet, gunky spots that ooze with slime — yuck! So we put grease between moving parts to keep them from getting all gunked up. Buy Grease In Saudia. The function of grease is to stay in contact and lubricate moving surfaces while resisting gravity or centrifugal force (or flopping out if you press it). The major advantage of grease is that it always slides along, no matter what the temperature is. Grease would be great for machinery and bearings, but not so much for power.