When adding of modifying content on the site you may notice toolbar with a set of icons above some of the text areas, these icons allow you to quickly insert pieces of XHTML code. This is particularly helpful for inserting links, images and videos.
You can use most XHTML tags and paragraphs/line breaks are added automatically. Links, and images and video embedding need a specific format to work so it's best that you use the editor icons to insert these with the correct format. Always include the http:// part of any link.
Also note that most standard BBcode tags will also work.