The author 'divides' literature into three categories. [=the author says that there are three categories of literature]
The teacher 'divided' the class (up) into four groups. = The teacher 'divided' (up) the class 'into' four groups.
Two 'divides evenly into' eight. [=eight can be divided into two an exact number of times with nothing left over]
(..) He's there! Look what they've done! If it's fame you seek, Christian... ...I think you have it. You brought this misery on us, Locksley. Nottingham tries to divide us. We are divided, rich boy. I'm not blind as that old man. You're still trying to be lord of the manor. (..)1991 Robin Hood: Prince of Thieves