Any link can have a rel=author atribute attached to it. The other end of this link represents the author of the page that the link is coming from. Google is using this information to get authorship information and for that reason it is a good real estate marketing idea to make sure the rel=author html code is attached to links within your blogs and the blogs you contribute to.
What do people get if they are using the authorship attribute?
Hope to use this information as a ranking signal at Google and to establish the credibility of authors. Right now, your photo may show up next to your results if you are using the rel=author markup.
What do people need to do now to take advantage of rel=author?
Having an author photo next to your articles makes the web much more human and trusted, and you get it by adding the rel=author markup.
For a single author blog – Google profiles are being used to get the picture and author’s information. Put it in every page of your website, maybe at the footer and you can wrap it around an image. You have to link back from your Google profile to the website.
For a multi-author blogs – At the bottom of each post have the author include a link back to their website. Point from the post to the Google profile. A lot of sites have author bios, add rel=author, and at the Google bio add rel=me and the confirmation link from the Google profile.
Requires a Google Profile and webmasters to insert the html. That’s it!