Example sentences
hòu后miàn面yǒu有rén人。
There's someone behind.
yín银xíng行zài在xué学xiào校hòu后miàn面。
The bank is behind the school.
About this word
后 is "back, rear" and 面 is "side, surface", so 后面 is literally "the back side". 面 is the productive half: 前面, 上面, 下面, 里面, 外面 all follow the same recipe of direction plus 面, which is why learning one gives you the whole set. Watch the split between space and time. 后 also covers "after" in 以后 (later) and 后天 (the day after tomorrow), so 后面 is for physical position, as in 房子后面, behind the house. The everyday pattern is 在…后面: 他坐在我后面. It can also mean the later part of something, like the back of a book.
The story behind the character
后
The traditional 後 is 彳 (walking) plus 幺 and 夂. It meant to fall behind, to lag. Xu Shen wrote 后, 迟也: "late."
面
面 is a face with an eye in the middle. Xu Shen wrote 面, 颜前也. The front of the head. Only later did it stretch to mean "side" or "noodle."