Background-attachment — htmlcss

The background-attachment property is used in CSS and certain HTML elements. If a background-image is specified, this property determines whether that image's position is fixed within the viewport, or scrolls along with its containing block.

Values

scroll - If specified, the background image will scroll within the viewport along with the block the image is contained within.
fixed - If specified, the background image will not scroll with its containing element, instead it will remain stationary within the viewport.

HTML example:

<body style="background-image:url('Wiki.png'); background-attachment:scroll;">
Body content.
</body>

CSS example:

body {
      background-image:url("Wiki.png");
      background-attachment:scroll;
}