7.3 Avoid movement in pages

Moving content, such as scrolling text, can be distracting and interfere with an individual’s ability to focus on relevant content, or the individual may read more slowly than the scrolling speed. It is important that users be able to freeze the movement of text.

If you have content that moves, note the following:

• The <marquee> tag is not in any W3C standard. Don't use it
• Loop an animated gif just once. Don't run the animation continuously
• Make sure that users can pause or stop moving or scrolling objects