1. Convert the equation into a GIF file and display it as an image. Because screen resolution is limited, subscripts and superscripts may not be legible unless the size for main-line symbols is 24 points.  The following equation was prepared in Corel Draw(R), exported as a BMP file and converted to an GIF87a file using LViewP1B.
     Example:

Problem: The graphic file may not fit in well with the rest of the text, and the use of dozens of graphic files in an HTML file increases the load time considerably.
Suggestion: Limit the use of this option to multi-line equations or complex super and subscript combinations.

2. Use graphic elements for the symbols In preparing your article for EPRT you may use the transparent gif images of the Greek alphabet -- and many other symbols in several sizes -- [we shall have a link to a descriptive table here later] that were produced by Karen M. Strom of the Five College Astronomy Dept. These files have been approved for ERPT use through the courtesy of the developer. If you wish to use them elsewhere, please consult the original distribution site at the University of Massachusetts, http://www-astro.phast.umass.edu

     Example: x_bar = a_crit <img src = "mu.gif"> ²
      + <img src = "Sum.gif"> _i=1 ⁿ
  i² / (1 - e ^{t / t0})

     is displayed as x_bar = a_crit ² + _i=1ⁿ  i² / (1 - e ^{t / t0})

Problem: The HTML required is rather lengthy and several GIF files may need to be loaded.
Suggestion: Use this only if the HTML phrase will fit on a few lines.

3. Use HTML to construct the equation.  Superscripts and subscripts can be produced using <sub> and <sup>. The symbol font can be invoked to get greek and other symbols, so that the HTML phrase <FONT face=symbol>a,b,g</font> will display as a,b,g. In HTML 4.0 many symbols can be displayed using an ampersand, the pound sign, a number, and a semicolon, -- as in &#130; -- but most current browsers cannot interpret this code.

     Example: x_bar = a_crit <FONT face=symbol>m</font> ²
      + <FONT face=symbol>S</font>_i=1ⁿ
  i² / (1 - e ^{t / t0})

     is displayed as x_bar = a_crit m² + S_i=1ⁿ  i² / (1 - e ^{t / t0})

Problem: The HTML required is rather lengthy.
Suggestion: Use this only if the HTML phrase will fit on a few lines.

4. Use a standard mark-up convention to represent the equation.  Use an underscore _ before a subscript, a caret ^ before a superscript, and square brackets for a symbol or Greek letter, as in [sum] or [mu].

     Example: x_bar = a_crit * [mu]^2 + SUM{i=1 to n} i^2 / (1 - e^(t / t_0))

Problem: This doesn't look very neat.
Suggestion: Use this only if the marked-up representation will fit on a single line.

5. Insert a MicroSoft® Word, WordPerfect®, Adobe Acrobat® or other file which the user can download and open to display the equation(s).  This only works if the user has the software to decode the file. Often free software is available to aid the user, but it can be a nuisance to download and store the several megabytes of code required.

     Example: a Word 6.0 file

Problem: The user has to have the correct display software.
Suggestion: Use this approach only when there are several pages containing many equations so that use of the other options would be cumbersome.