Avoid use of obsolete language features if possible.
Deprecated elements are ones which have been replaced by newer elements.
While browsers currently support those elements, they may not in the future. It is best to avoid use of these elements when possible. Be aware that designing stylesheets to fail gracefully, required under Checkpoint 6.1, may require you use deprecated elements, but do so with caution. Often these features have been removed because of compatibility issues and replaced with elements that are more compatible with a wide range of browsers and access devices. It is good practice to use the newer alternatives whenever possible.