I wanted to draw some waveforms for my NEC IR decoder for SparkCore post. I suppose I could have drawn them by hand, or maybe researched some hopefully free software that would make drawing them easier. I did not do that, however.
SVG is the scalable vector graphics image format. Unlike formats like JPEG or PNG, it specifies lines, arcs, and text mathematically rather than by pixel, so you can zoom in. And when you print, the text is always clear and printed at the full resolution of your printer.
Keith Wood's jquery.svg for creating SVG images
FileSaver.js for locally saving the SVG images
You can view the sample site here.
And, finally, the library. It's pretty straightforward, I think.