A few nice image website images I found:
Website Graph
Image by Nikita Kashner
What do the colours mean?
Blue: for links (the A tag)
Green: for the DIV tag
Violet: for images (the IMG tag)
Yellow: for forms (FORM, INPUT, TEXTAREA, SELECT and OPTION tags)
Orange: for linebreaks and blockquotes (BR, P, and BLOCKQUOTE tags)
Black: the HTML tag, the root node
Gray: all other tags
Make your own graph: www.aharef.info/static/htmlgraph/
