b ± Sqrt(b^{2}  4ac)
x = 
2a
The equation above has been rendered in HTML code alone. Here's the code:
<b>
<pre>
b ± Sqrt(b<sup>2</sup>  4ac)
x = 
2a
</pre>
</b>

Pro:
This is an appropriate choice if you only need to display simple expressions.
It's convenient because
you don't have to leave your HTML editor of choice, and the only code you
have to know is standard HTML.

Con:
Using this method severely limits what you can display with the usual notation. Since there's no way of representing a square
root symbol in HTML, you must rely on your readers to recognize nonstandard
notation (like "Sqrt()" in the example above). The same thing goes for integrals,
summations, matrices, and any other complicated math notation.

References:

Math Notation with ASCII
Tips on how to display math using only the standard character set.
Bare Bones Guide to
HTML
Find out what you can and can't do with HTML code. In particular, read
through the list of special
characters supported by HTML.
