Its not that you aren't supposed to use it, its just a convention thing you should really only stick to one emphasis type (or maybe two when absolutely necessary). 

For printed material I prefer italic however I don't find it stands out enough when reading online so I use bold. In printed material CAPS are never acceptable except for titles and bold is used almost as rarely.

The rules of graphic design are broken online even by experienced designers very often. We are still in the process of defining online conventions as an information age society as a whole. I've read lots of material by internationally recognized art directors and designers on what those conventions should look like, and they are all based on traditional print material with just a few exceptions like font size, kearning and leading.

My opinion is that the conventions will work themselves out through usage for good or bad in the long run. Society as a whole dictates what looks good to them online. Unlike in the past when printed material was strictly controlled by publishers.

<strong>bandolin</strong><br />
[Former 3DS Max forum coordinator]<br />
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