A background image appears behind the text on a page. By default, the image is tiled to fill the page and scrolls with the page.
Unfortunately, there are plenty of examples of ineffective or distracting backgrounds on the Web. Here are some tips for making yours better than those:
Choose images that are designed to be tiled so that each copy blends smoothly into the next. When the image’s edges blend well, it will look like a single, large image. In the following figure, the edges do not blend well:
On the other hand, the edges of the tiled copies of the following image blend together well in both directions.
Use subtle ...