Use and licence
Every design on this site is generated by a program from geometry. Nothing is traced from, derived from, or based on anyone else's artwork, and no third party holds a claim on any of it.
You may print these, photocopy them, hand them out in a classroom, put them in a workbook, sell what you make from them, and use them commercially. No attribution is required and no permission is needed.
The one thing worth saying plainly: the files themselves are not for resale as a stock pack.