The background property is a shorthand property for setting all background properties in one declaration.
body {background: #FF0000}
body {background: url(stars.gif) no-repeat top}
body {background: #00FF00 url(stars.gif) no-repeat fixed top}
This shorthand property allows to declare all background properties in one single declaration line.
The following, are the properties that can be set using the background shorthand property: background-color, background-position, background-size, background-repeat, background-origin, background-clip, background-attachment, and background-image.