The term "Presentation" refers to how an element looks. This includes properties like its color, size and text alignment.
It was common to use presentation attributes for elements in older versions of HTML. For example:
HTML5 however, tries to keep Presentation separate from document structure and content.
In HTML5, many presentation elements and attributes should no longer be used. These elements and attributes are said to be "Deprecated" or "Obsolete".
A "Deprecated" item will probably be removed from the language in the future. So they should not be used in new pages. Presentation attributes should be replaced with the "Style" attribute or CSS Style Rules in existing pages.
An "Obsolete" item is no longer supported and must not be used. It is common to deprecate an item first to give developers time to convert their existing pages.
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