If you've cruised through Amazon's book descriptions, you may have noticed some that are more complex than others. While some descriptions are very basic with black text, others have text in bold, italics, and even orange text. It turns out that you can use HTML code in book blurbs. In case you're not familiar with it, here's some HTML code authors can use to make their descriptions stand out.
Bold: <b>Your Text Here</b>
Italics: <i>Your Text Here</i>
Centered: <center>Your Text Here</center>
Largest: <h1>Your Text Here</h1>
Large and Orange: <h2>Your Text Here</h2>
Underlined: <u>Your Text Here</u>
There are a few more, but I think those are the most useful. Of course, you don't want to overuse it, because that would make it look silly.