Check out example codes for "background image in 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

<style>
body {
  background-image: url('img_girl.jpg');
  background-repeat: no-repeat;
  background-attachment: fixed;
  background-size: cover;
}
</style>

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

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

Code Example 6

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

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