css adding background image from file

1/* The first method using an image on your server */
2background: url('img/someimage.jpg');
3
4/* The second method using an image hosted on another server */
5background: url('http://www.someimage.com/someimage.jpg');
6
7/* A third method that allows the site to determine protocol instead of explicitly defining it */
8background: url('//www.someimage.com/someimage.jpg');