Karl is a math and chemistry high-school teacher. He used to create the graphics in his worksheets and
exams using LATEX's {picture} environment. While the results were acceptable, creating the graphics often
turned out to be a lengthy process. Also, there tended to be problems with lines having slightly wrong angles
and circles also seemed to be hard to get right. Naturally, his students could not care less whether the lines
had the exact right angles and they nd Karl's exams too dicult no matter how nicely they were drawn.