What is Edge ?
Edge is (noun) 1. a side of something flat He put his plate down on the edge of the table. She lay down on the roof and looked over the edge. You can stand a £1 coin on its edge. The axe has a very sharp edge. 2. a line between two quite different things He lived in a house at the edge of the forest. The factory is built right on the edge of the town. 3. an advantage to have the edge on a rival company to have a slightly larger share of the market than another company 4. on edge nervous or jumpy Everyone was on edge, waiting for the telephone call. (verb) to move in a slow, careful way He started edging towards the door.
source: Easier English, Student Dictionary Upper Intermediate Level