There seem to be a lot of tutorials on the web about D3 (www.d3js.org). However I've yet to find one that explains,simply, how to create a line chart. They all seem to be overly complicated, don't explain exactly what is happening, or call functions, classes and variables by the same name.
So here's my attempt. It took me a good few hours to get this working, which is pretty poor given that what I achieved is extremely simple.
