Check out example codes for "add background image in css". It will help you in understanding the concepts better.

Code Example 1

html,body {
  background-image: url("your.picture");
}

Code Example 2

.w {
background-image: url("images/tom1.png");
}

.a {
background-image: url("images/tom2.png");
}

.s {
background-image: url("images/tom3.png");
}

Code Example 3

background-image: url("photographer.jpg");

Code Example 4

body {

 background-image: url("paper.gif");

 background-color: #cccccc;

}

Code Example 5

background-image: url("image.gif");

Code Example 6

/* Answer to: "add background image css" */

/*
  The background-image property sets one or more background images
  for an element.

  By default, a background-image is placed at the top-left corner
  of an element, and repeated both vertically and horizontally.

  Tip: The background of an element is the total size of the
  element, including padding and border (but not the margin).

  Tip: Always set a background-color to be used if the image is
  unavailable.
*/

/* Set a background-image for the <body> element: */

body {
 background-image: url("paper.gif");
 background-color: #cccccc;
}

/* Set two background images for the <body> element: */

body {
  background-image: url("img_tree.gif"), url("paper.gif");
  background-color: #cccccc;
}

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