Oh it's just a base64-encoded JSON that contains other parameters like the view limits and such. You can base64 decode itself and see.

Oh yeah that's neat, what does the type: 0 mean?

I guess as an aside did you write the plotting part or used some library?

I wrote the whole thing from ground up. I don't think I remember seeing any libraries back then. It actually initially used 1-pixel DIVs, then SVG, then later changed to canvas.

type:0 just means a regular y=f(x) function

wow well that's really impressive, the 1px divs sounds interesting