Avoid making anything flicker

Requirement: No item on a page should flash or flicker. The <blink> tag should not be used.

For people with photosensitive epilepsy, items that blink at a certain frequency can induce seizures.

For many users, blinking text can be very annoying in that it is difficult to read.

Most users find anything that automatically and uncontrolably moves or flashes on a page distracting.

For all these reasons, avoid using the <blink> tag. Also avoid fast moving animated gifs and other presentations. If motion is important to a presentation, give the user the ability to start, stop or skip it so that it does not become a distraction or health risk.

General considerations about design

Many people confuse distraction and attraction. Generally, good layout attracts readers to particular parts of a page at the proper time. Think of good highway signs, how they are positioned over the right lanes, how they appear consistently and are worded clearly. Diagrams and words are large with enough space around them so that everything is readable.

Now think of of stepping into a food court at a mall. Every sign is different, many might be blinking or flashing, menu items are crammed into small spaces. All this activity is to divert your attention from where you were to the food court. Once in the food court, each store competes with the other in an effort to garner your your interest and dollars.

The method here is mostly distraction as is proven by the number of people who wander from station to station because they have to focus on specific sections to determine the offerings and the prices.

While distraction might be a good marketing approach in the world of fast food, it does not work on the Web. The Web is not an impulse tool. It is a tool for sharing information. Like on the highway, Web users travel with a final destination in mind -- a piece of information, a purchase, a submission of data.

Unlike at the food court, where we might stand in front of a dozen options at once, waiting for one to jump at us, Web sites generally are viewed one at a time. Rarely are we looking for anything to come to us as much as we are looking for a way of getting to it.

For these reasons, the most successful Web sites tend to be well organized and favor simplicity over complexity.