Khanh

Fields is a WordPress plugin that let you manage write panels in your write/edit page. Fields supports post types that can have UIs.
With Fields, you can define boxes which appear in your write panels. A box can contain a number of groups which are sets of custom fields that you can define. Boxes are displayed as meta boxes and groups are shown as tabs that can be switched inside boxes. Within a group, fields can be shown as either textfields, textarea, drop boxes, radio group or check boxes.
Fields does not create custom post types, to do so, use other plugins such as WP Post Type UI.
Brief structure of Fields:
<ul>
<li>Fields can be: textfield, textarea, select (drop box), radio group and check boxes</li>
<li>A group contains fields</li>
<li>A box contains groups</li>
<li>You can choose which groups a box should include and which post types a box should appear in</li>
</ul>

Fields

Creates custom write panels to manage post custom fields.

Vadym

Extra User Details is the simple plugin that allows you to add extra fields to the user profile page (e.g. Facebook, Twitter, LinkedIn links etc).
Extra fields can be easily accessed in your templates like a general wordpress author details:
<pre><code><?php the_author_meta('meta_key'); ?>
</code></pre>
Plugin saves fields data in wp_usermeta table. You can add and edit extra fields at plugin options section in backend.

Extra User Details

Took me a bit to get this out, since there is no help online.
I wrote a little function and pasted it into my functions.php:
function extra_user_info() {
		global $current_user;
			get_currentuserinfo();

		echo 'Your extra user info is' . $current_user->PUT_YOU_ID_HERE ;      		

	}

add_action ('NAME_OF_HOOK_WHERE_YOU_WANT_IT', 'extra_user_info', 20);


How to display the correct values in the frontend

Add extra fields to the user profile page, saved in WordPress' native way (in wp_usermeta).

Fields vs Extra User Details