Bonus feature: it occurred to me that non-Zangband players reading this might be confused by the references to magic schools. Vanilla has priest spells and mage spells, and that's it; Zang has seven schools of magic, chosen at character-creation. Mages can pick any two schools; other classes have more restricted choices. (Rangers have to pick Nature; paladins have to pick either Life or Death). Each school only has four books, and you can never learn spells from books outside your chosen schools, but there's a certain amount of overlap.

Specific schools will be covered in forthcoming updates, oriented towards new Zangband players who don't want to end up with unfavourable school combinations. I don't claim to be an expert: in particular, this analysis doesn't take much account of very high-level play, because (in case it's not already apparent) I don't do a whole lot of that. Anyway, here's the first: