Cover means a shelter or to conceal. It is a pigment or a thing or an object lied over or around something which needs to be closed or hidden. It is this capacity of a pigment to make an underlying surface hidden is called a cover.  In art, a cover art is an artwork illustrated or depicted outside a published work or a product. Such cover art usually consist of a photograph which can be seen as a cover picture of a magazine, music album, book, movie CD etc. This art is displayed in order to promote that product, and is usually attractive and artistic.