Coping is used to separate the pool structure from the pool decking.
There are two main options for coping: Bullnose or cantilever.
Bullnose coping is aluminum and often either rounded or flat faced. Bullnose coping allows you to pour concrete straight up to the pools edge. White and gray are the primary color options.
Cantilever coping is a flat track. You would use this when applying bricks or stones around the pools edge. You may also couple it with foam forms and simply pour concrete, then remove the forms to reveal a simple, curved concrete edge.