An absolute URL directs you to a specific file or directory that is indepent. An example would be http://www.google.com/. A relative URL directs you to a file or directory that is in relation with an already present file or directory.
The files panel is great for organizing all of the files on your site and creating new files and folders. It can save a lot of time because Dreamweaver can automatically update changes you have made.
The first HTML page that you create is known as the index.html page. This is the first page the browser loads automatically when a visitor goes to the site.
XHTML 1.0 Transitional.
They are preferred because they are better handled by screan readers used by visually impared users. Bold and Italics are more for style and should be handled only in CSS.