In this week's Problem of the Week, you get to know Particle Man. As you'd expect, he does the sorts of things a particle can. What's he actually like? What makes Particle Man tick? It's not important. Particle Man.
And then you will explore the deep-seated enmity between Particle Man and his arch-nemesis, Triangle Man. Spoiler alert: They have a fight and Triangle wins. Triangle Man.
Actually, you're not going to do any of that this week, but I thank They Might Be Giants for saving me from having to write an actual intro. Click here to try this week's Problem of the Week, about the motion of a particle (man).