This is the content area of your web page. For now it contains this filler text to help you visualize what your web page will look like when it's complete. Replace this text with your own text (and graphics). Here's an example of the link text color in the content area.
To find this section in the HTML source code, open this page in any text editor or HTML editor and do a search for the phrase "Begin Content". If you're using Internet Explorer, then you can open the HTML source code in Notepad by simply clicking on View » Source.