The Text Widget is an advanced widget that allows you to use your own code (HTML) in your sidebar. The sky is the limit, if you can build it in HTML, you can display it on your sidebar.
What is does
The next box down is where you will enter your text or type/paste your HTML code. Please note that scripts including iframes will not work in the widget.
Finally, if you would like the widget to automatically create spaces when you hit return, check the box that says AUTOMATICALLY ADD PARAGRAPHS to enable that.