Scalable vector graphics

Just Vector Graphics to its friends

The SVG format is the Grand Central Station of vector graphics, with junctions to PDF or and the other compatible formats like as Adobe Illustrator, EPS and xfig.

pdf2svg

pdf2svg is handy used in conjunction with (almost) any of the other programs to convert between formats.

Inkscape

Open source Inkscape can do everything, although I find its Adobe Illustrator pretensions (perhaps unfairly) grating. Aimed firstly at general vector graphic design, which means the functions you want for sciency stuff are not front-and-center, but it can be done.

Boxy

A fresh option leveraging web technology is Jarosław Foksa’s Boxy.

Minimizing

Victor Zhou points out that you can minimize rather bloaty SVGs using svgo

npm install -g svgo
$ svgo test.svg -o - | gzip -cfq9 > test.svgz