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

Code Example 1

background-image: url("image.png");
background-position: center;
background-repeat: no-repeat;
background-size: cover;

Code Example 2

div {
  background-color: #ffffff;
  background-image: url("img_tree.png");
  background-repeat: no-repeat;
  background-attachment: scroll|fixed|local|initial|inherit;
  background-position: right top  |  x% y%  |  xpos ypos;
  background-clip: border-box|padding-box|content-box|initial|inherit;
  background-size: auto|length|cover|contain|initial|inherit;
}
//shorthand:
div {
  background: #ffffff url("img_tree.png") no-repeat right top;
}

Code Example 3

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

Code Example 4

body {

 background-image: url("paper.gif");

 background-color: #cccccc;

}

Code Example 5

.selector {
  background-image: url(image.png);
}

Code Example 6

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

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