Tile coving refers to a type of trim that is commonly used on wall and floor tiles. The cove base is a ceramic barrier that provides a rounded transition between the floor and the wall. Cove bases make tiles much easier to clean and are considered mandatory for commercial buildings such as hospitals, industrial bathrooms and kitchens. The methods of tile coving make the tiles more sanitary because dust and grime does not collect as much and when it does, it's easier to clean.
Sanitary cove base
Commonly used for floor trims, the sanitary cove base has a rounded, finished edge, similar to that of a bullnose, to cover up the body of the tile. Although bullnose doesn't involve coving, it is sometimes substituted for a cove base. Sanitary cove tiles can be applied to the inside and outside corners.
Rounded-top cove base
The rounded-top cove base is just as described---the finished top is rounded in a similar fashion to that of the bullnose. However, this type of cove base is typically used in a areas without wall tile.
Stack-on cove base
The stack-on cove base is used for wall trips. It provides coving on the bottom, complete with a flat edge on top to accommodate wall tiles.