The third are utility pages. Utility splash pages may be used when the actual site requires content that is slow loading, or needs some kind of explanation. This doesn't tell you much about what an URL does. The URL of a web page is its specific address. If you type this URL or address into the appropriate area on your browser you will be lead to this page.
Sizes vary, but generally they are rectangular and located on the top of a web page.
When you hear the term 'banner advertising' this is a reference to the practise of paying for the placement of banners on various relevant web sites. You will most likely notice a framed page when you see more than the standard right hand scroll bar. Another sign that you are visiting a site with framed pages is when you scroll up and only a portion of the visible content moves. Markup Language is the language of the World Wide Web. This series of tags used to mark up plain text is what creates linked pages.