Rhys Wynne

This plugin adds to Profile Pages an extended “Author Bio”. This allows users to add more information to what they’d feel comfortable adding underneath the post. This Author Bio can be displayed on the author page, as opposed to the standard “Author Description”.
This plugin is a framework, so requires a bit of PHP skill and experience in template editing to make it work.
<ul>
<li>For more features including Google Rich Snippet Integration, check out <a href="http://bloggingdojo.com/wordpress-plugins/author-plus-premium-wordpress-plugin/" rel="nofollow ugc">Author+ Premium WordPress Plugin</a></li>
<li>Blogging Tutorials and WordPress Plugins at <a href="http://bloggingdojo.com/" rel="nofollow ugc">The Blogging Dojo</a></li>
</ul>
<h3>Usage Instructions</h3>
The best place to use this plugin is on the author.php page. I have included a framework for using this plugin.
To begin with, on <code>author.php</code>, add this line. This will get the information on the author.
<pre><code>$author = wp_authorplus_get_user_on_author_page();
</code></pre>
You can then use the standard <code>echo $author->display_name;</code> and similar notation as shown in (The WordPress Codex)[https://codex.wordpress.org/Author_Templates#Using_Author_Information].
To call the extended author descriptions, use <code><?php wp_authorplus_extended_author_bio($author->ID); ?></code> anywhere outside the WordPress Loop, but after you declare $author on wp_authorplus_get_user_on_author_page().
Any questions, please <a href="http://bloggingdojo.com/contact-us/" rel="nofollow ugc">Contact Me</a>

Plugin Name:  Author+ (Lite)

This plugin adds to Profile Pages an extended "Author Bio". This allows users to add more information to what they'd feel comfortable a …

mattdu

This plugin uses the custom taxonomy features of WordPress to create “bylines” — essentially, tags representing authors who contributed to a post. The differentiating feature of this plugin is that it should not require any modifications to your theme files (assuming it is already displaying the post author).
This plugin would be useful for publishing situations where the majority of your content is from contributors who you don’t necessarily want to have access to your back-end. It still conveys the appearance that the authors are members of the site (it provides a built-in archive page for each Byline). If your theme displays tag descriptions, you could use the Byline description field to identify guests vs. “staff” writers or provide other author information.
You can see an example of this plugin at work at http://thedailycougar.com

Byline

The Byline plugin is simple and suitable for multi-author WordPress sites.

Best For Multi Author

Solves the co/multi-author problem without modifying the theme. Uses a custom taxonomy, "Byline," that replaces the Display Author.

Plugin Name: Author+ (Lite) vs Byline