SUP - Superscript

Summary

Syntax	<SUP>...</SUP>
Attribute Specifications	common attributes
Contents	Inline elements
Contained in	Inline elements, block-level elements

Details

The SUP element is used for superscripts. Since SUP is inherently presentational, it should not be relied upon to express a given meaning. However, it can be useful for mathematical exponents where the context implies the meaning of the exponent, as well as other cases where superscript presentation is helpful but not required. For example:

• The rent is due on the 1<SUP>st</SUP> of each month.
• An example of a quadratic polynomial is <STRONG>3<VAR>x</VAR><SUP CLASS=exponent>2</SUP> + 5<VAR>x</VAR> - 7</STRONG>.

The following two examples are ambiguous when presented on a browser incapable of superscript text:

• 2<SUP CLASS=exponent>4</SUP> = 16
• sin<SUP CLASS=exponent>2</SUP><VAR>x</VAR> + cos<SUP CLASS=exponent>2</SUP><VAR>x</VAR> = 1

There is no simple solution for this problem. One could use notation such as 2^4 to represent "two raised to the exponent four." If it gains browser support, MathML should provide a more suitable solution in the future.

More Information

• SUP in W3C HTML 4.0 Recommendation
• SUP in W3C HTML 3.2 Recommendation
• SUP in WDG HTML 3.2 Reference
• SUP in Learning HTML 3.2 by Examples

Copyright © John Pozadzides and Liam Quinn. All rights reserved.