It's basically footnotes. Useful as a reference but not necessary to read cover-to-cover. Like, there's a part in the "Cyclops" episode that's a few pages of ridiculous names, and Gifford tells you what they're referring to. But you don't need to know that Schwanzenbad-Hodenthaler means "penis in bath, inhabitant of the valley of testicles" to know that it's a funny name.
It's basically footnotes. Useful as a reference but not necessary to read cover-to-cover. Like, there's a part in the "Cyclops" episode that's a few pages of ridiculous names, and Gifford tells you what they're referring to. But you don't need to know that Schwanzenbad-Hodenthaler means "penis in bath, inhabitant of the valley of testicles" to know that it's a funny name.