If there are many horizontal rules on a multi-screen page, each segment of the page can begin to look like the others, possibly confusing a reader trying to navigate the document. Use bars with smaller image file sizes rather than larger, and use a small set repeatedly, rather than a large number only once each, to maximize use of the browser image cache. Use a small set of bullets or accent graphics repeatedly, rather than using a large number only once each Because many HTML browsers cache images as they are loaded, you can achieve fairly fast download times if the images you require are mostly loaded from the image cache rather than being downloaded repeatedly. Using many unique images, or identical images with differing names, negates this advantage, as well as having a potentially disunifying affect on your document. Understand the pitfalls of changing the default text color for a page Explicitly setting the text color on a web page comes with some interesting human costs.
Computer displays provide much poorer fidelity than do paper-based media.
The designer's options for using subtle nuances of color and type to improve the readability of a design are severely curtailed when working with 256-color, medium resolution computer displays.