Well, Frankenstein is the name of the scientist, Victor Frankenstein, who creates the monster. Congratulations: you now know more than the average Joe, who thinks that the scientist creates a monster named Frankenstein. Did Shelley know that her nameless monster would end up getting called Frankenstein? We're not sure, but given how important he is in the book, we think it's a strong possibility.
Now let's get to the good stuff. The book's subtitle is "The Modern Prometheus," a reference to Classical myth about a Titan named (surprise!) Prometheus. Prometheus makes man (as in, the first man) out of clay—and then makes the big mistake of stealing fire from the Gods so that man can, you know, survive. And then he's punished in a ridiculously painful manner involving birds tearing out and eating his liver. Every single day.
What does this have to do with Frankenstein? Well, a lot. First, check out "Symbols" for our thoughts on fire. And then come back (we'll wait), and think about how Victor Frankenstein decidedly doesn't take care of the monster the way Prometheus cared for man. And then prepare to have your mind blown when you learn that the philosopher Immanuel Kant called Ben Franklin the "Prometheus of modern times" in reference to his experiments with electricity (source). Franklin —Frankenstein —does that spark (groan) any ideas?