Deprecated Elements or Attributes

Over the course of the development of the Internet, styling rule have gone through several iterations. There are terms that are no longer in conformance with the current W3C recommendations. These terms are referred to as "deprecated".

Per the W3C: "A deprecated element or attribute is one that has been outdated by newer constructs. Deprecated elements are defined in the reference manual in appropriate locations, but are clearly marked as deprecated. Deprecated elements may become obsolete in future versions of HTML."

It is recommended that browsers continue to support deprecated elements due to the large number of older web pages still active throughout the Internet and for reasons of backward compatibility.

As a web developer, one should recognize these attributes and be familiar with there effects, but make it a practice to not introduce them into your web pages.

Obsolete Element or Attribute

Obsolete Elements are those where there is no guarantee of support by user agents (browsers, etc). Obsolete elements are no longer defined in the W3C specifications.