When you work online, words are like clothes: Use them carelessly, and you might as well show up for a business meeting in dirty flip-flops and an "I'm with stupid" T-shirt.

Fortunately, Firefox makes it easy to spruce up your online "wardrobe" with all sorts of language-enhancing features. Today I'll focus on the most important ones: Its spell-checking support and dictionary extensions.

All of the Firefox 2.x and 3.x browsers include built-in spell-checking support; although it is enabled by default, you can double-check by looking here:

1. Click on the "Tools" menu.
2. Click on "Options" (usually about two-thirds of the way down the list).
3. Select the "Advanced" tab.
4. Select the "General" tab.
5. Make sure the "check spelling as I type" option (it's the sixth option down the list in Firefox 3) is checked.

If you still use a Firefox 1.5.x browser, simply install the SpellBound extension to add spell-checking support to your browser.

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