how to add a background image in html

<!-- HTML -->
<div id="imageDiv"></div>

<!-- CSS -->
  #imageDiv {
	background-image: url('someimage.png');
</style><!DOCTYPE HTML>
<html lang=us>
  <meta charset=UTF-8>
  //the following code within the style tags is CSS.
  /*this is a body tag. After specifying 
  that we want to affect the whole body,
  we add {}, and write the background color
  we want to change it to. */
  /* this is a class, which we have named green. we add {}, then
  write the background color we want.*/
   /* this is an id, which we have named blue. we add {}, then
  write the background color we want.*/

This background is red.
  // you must make sure to note that when you add a background to
  a paragraph, you must add a class or id, name it, then style it 
  as seen above.  with tags HTML already recognizes, however, you 
  don't have to do anything more than shown above.
  <p class="green">
  This background is green.</p>
  <p id="blue">This background is blue.</p>



.selector {
  background-image: url(image.png);
background-color: url('url from web');

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