Shortcodes can be used to embed dynamic content into any area that supports them, like a post, text widgets or the footer section.

Atom shortcodes

[query]

Read its documentation page for a detailed description.

[widget]

Read its documentation page for a detailed description.

[link NAME]

Valid names are: wp (WordPress.org), rss (RSS Feed), login (Dashboard Login), theme (Theme URI), html (HTML Validator), css (CSS Validator)

[member]
CONTENT
[/member]

Show the given content only to site users. Props to Justin Tadlock for these shortcodes.

[visitor]
CONTENT
[/visitor]

Show the given content only to unregistered visitors.

[tinyurl URL]

Get the short version of an URL, using the TinyURL service.

[credit]

WordPress & Theme credits.

[copyright]

Copyright message. Eg. “My Site © 2011″

[load]

Displays the page load time and the number of database queries performed (until the shortcode is processed).

[field NAME]

Get the value of a custom field from the current post

[pagerank URL]

Get the Google PageRank ™ of an URL

[subs SERVICE id="ID"]

Get the subscriber count from the given service. Supported services are: Twitter (followers), Youtube, FeedBurner, Facebook (likes). The ID is required, and represents your user ID for that service.