Physical and Logical Tags

Cont. Tutorial 1

Character Tags

A tag that you apply to an individual character is referred to as a character tag. There are two types of character tags, physical and logical.

Physical Tags

Physical tags are used to indicate exactly how specific characters are to be formatted.
The syntax or format for using a PHYSICAL TAG is as follows:

<Tag Name> Characters to be formatted. </Tag Name>

Examples of Physical Character Tags

<B>	Indicates that the text should be bold.	</B>
<I>	Indicates that the text should be italic.	</I>
<TT>	`Indicates that the text should be used with a font such as Courier that allots the same width to each character.`	</TT>
<BIG>	Indicates that the text should be displayed in a big font. Available in HTML 3.0 or higher.	</BIG>
<SMALL>	Indicates that the text should be displayed in a small font. Available in HTML 3.0 or higher.	</SMALL>
<SUB>	Indicates that the text should be displayed as a _subscript, in a smaller font if possible. Available in HTML 3.0 or higher.	</SUB>
<SUP>	Indicates that the text should be displayed as a ^superscript, in a smaller font if possible. Available in HTML 3.0 or higher.	</SUP>
<U>	Indicates that the text should be displayed underlined. Not all browsers support this tag.	</U>

Logical Tags

Logical tags are used to indicate to the visually impaired that there is some emphasizes on the text. Each browser has its own technique as to how to indicate to its viewer that the text between the tags are different.
The syntax or format for using a LOGICAL TAG is as follows:

<Tag Name> Character/s to be formatted. </Tag Name>

Examples of Logical Character Tags

<EM>	Indicates that characters should be emphasized in some way. Usually displayed in italics.	</EM>
<STRONG>	Emphasizes characters more strongly than <EM>. Usually displayed in a bold font	</STRONG>
<CODE>	`Indicates a sample of code. Usually displayed in a Courier font or a similiar font that allots the same width to each character.`	</CODE>
<KBD>	`Used to offset text that the user should enter. Often displayed in a Courier font or a similiar font that allots the same width to each character.`	</KBD>
<VAR>	`Indicates a variable. Often displayed in italics or underlined.`	</VAR>
<CITE>	Indicates short quotes or citations. Often italized by browsers.	</CITE>

The big question is when should you use a logical verses a physical tag?

I recommend to my students to use logical tags whenever possible, so your pages are more accessible to the visually impaired.

Continue with Special Characters or return to top of this page.