For the uninitiated: a XKCD comic strip, which is drawn on the one hand stick figure is -so do not expect any graphics wonder where I like the Spartan style. Above all, the comics deal but with a lot of science, "Nerdculture" and IT. The very first comics are sometimes not at first glance to understand if you are not familiar with the corresponding areas. So I often have shrugged because I had no idea where the joke was. But the jokes that are understood, do the rest loose up for (but I'm also a fan). So best: go on XKCD.com, read a few Probem and then decide.