Another D3 tutorial...

So here is another tutorial in D3.

Advice:
Just copy-paste this example in a file named "index.html" opened in your favorite editor and in a recent browser.

I have just done this using Word as my editor and it seems to work. 
Great news!!!

I am guessing that it's the script in the head of the page that calls the javascript library from http://mbostock.github.com/d3/d3.js

It puts a nice circle on the page and when I put my mouse over the circle it changes colour. 

This is a great start and represents a great step forward for me. 
Small step but great!

:-)