If you know HTML, you can use some codes in your forum posts. However, even if you don't know HTML, the codes aren't that hard to learn, so I have listed them below. You can often used these codes in blog posts and blog comments, too, which is handy.
The way that HTML works is that all codes are contained in brackets - the greater than/less than symbols. To apply a code to some text, you have to put the code before your text - it's like saying: start using this code now. Then, you have to put an 'end' code after your text, like saying: stop using this code now. The end code is like the beginning code, but it has a slash in it.
The only hard thing about HTML is that it's pretty picky - the codes must be spelled exactly right, all lowercase, and the symbols (<, >, /, ", ", etc.) have to be placed exactly the way they are shown below. To make it easy, you can just copy the text after "Usage:" and paste it in your forums posts, then replace the sample text with your own text.
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CODE: a
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What it does: Makes an underlined hyperlink and allows you to specify the text that shows
Sample: Dixie Pieces Home Page
Usage: <a href="http://www.dixiepieces.com/">Dixie Pieces Home Page</a>
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CODE: blockquote
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What it does: Makes an indented paragraph, just like they teach in typing class
Sample:
"And so, my fellow Americans: ask not what your country can do for you—ask what you can do for your country." - John Fitzgerald Kennedy, Inaugural Address, 1/20/1961
Usage:
<blockquote>"And so, my fellow Americans: ask not what your country can do for you—ask what you can do for your country." - John Fitzgerald Kennedy, Inaugural Address, 1/20/1961
</blockquote>========================
CODE: br
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What it does: Makes a line break, like hitting 'enter'. NOTE: this code is an exception because there is no 'begin code'
Sample:
Ask not what your country can do for you...
Ask what you can do for your country.
Usage:
Ask not what your country can do for you...<br />
Ask what you can do for your country.========================
CODE: code
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What it does: Formats the text to look like computer programming code, usually in a courier/typewriter font
Sample: If ($HeProposed) { print "say yes!"; }
Usage: If ($HeProposed) { print "say yes!"; }
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CODE: em
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What it does: Italicizes the text.
Sample: I didn't say that, but that's what I meant.
Usage:
I didn't <em>say</em> that, but that's what I <em>meant</em>.
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CODE: strong
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What it does: Bolds the text
Sample: They may not spend the night.
Usage:
They may <strong>not</strong> spend the night.
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CODE: img
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What it does: Displays an image
Sample: 
Usage:
<img src="http://dixiepieces.com/images/darkBlueSmFlower.gif" />
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Making Lists
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If you have those down, you're ready to make lists. The codes for making a list - like a bulleted or numbered list - are not complicated, but you have to use them in combination with each other. First, you encase your whole list in either "ul" (stands for "unordered list", or a bulleted list) or "ol" (stands for "ordered list", or a numbered list). Then, you have to encase each item of your list in "li" (stands for "list item").
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CODE: ul + li
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What it does: Makes a bulleted list
Sample:
- First bullet point
- Next bullet point
- Last bullet point
Usage:
<ul>
<li>First bullet point</li>
<li>Next bullet point</li>
<li>Last bullet point</li>
</ul>========================
CODE: ol + li
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What it does: Makes a numbered list
Sample:
- Item number one
- Item number two
- Item number three
Usage:
<ol>
<li>Item number one</li>
<li>Item number two</li>
<li>Item number three</li>
</ol>
