Search
A search form for your site. You may want this in a year or so when you have so much content (like Wikipedia.com) that people will want to search your website.
Tag Cloud
A cloud of your most used tags. This creates a word cloud of your most used tags. It's not a good idea to use it because it slows down your page load speed. If you want more information on word clouds then have a look at Marion Black's Training - Word Clouds...
Text
Arbitrary text or HTML. This is probably the most useful Widget I can think of. You can add text, video, images, custom lists, AdSense, affiliate links and more using the Text Widget. You'll find more geek-speak techie stuff at http://codex.wordpress.org/WordPress_Widgets#Using...
Related Training:
Adsense Without a Plugin
Affiliate Link Image in Text Widget
Wealthy Affiliate Banner in Sidebar Widget
Thanks for reading and bookmarking,
More Training by Marion Black - Sorted
As always I'm here to help you,