Some position words:
前边 qián - in front
后边 hòu - behind
左边 zuǒ - left
右边 yòu - right
上边 shàng - above
下边 xià - below
里边 lĭ - inside
外边 wài - outside
Explanation: Word order is different in Chinese from what it is in English. This is very important for forming sentences, including when expressing position.
If you want to describe the position of A in relation to B, in English you would say "A is PW of B", for example "The book is on top of the table". In Chinese the easiest structure is:
A is B's PW
or in Chinese: A 在 PW 的 PW
Some examples:
电脑在桌子的上边 - the computer is on top of the table (literally 'computer is table's upperside')
食堂在宿舍的前边 - the canteen is in front of the dormitory (literally 'canteen is dormitory's frontside').