I'd like to know more about it and what is its difference from preposition and some examples of this.
2 Answers
I think you are making a fundamental mistake. Your conscious or otherwise presumption is, Western Grammar is correct and it must therefore apply, without reservation, to Chinese. Words are placed in categories such as 'preposition', but words refuse to remain in their categories. This is true in Chinese and English.
And dear old Aunty Wiki blathers on about it, as if she knows by divine right.
What about 前?Is 前 a preposition? Well, that just depends on how it is used and who is translating.
会议向前提了。
meeting to front/forward carried
The meeting has been brought forward.
我只读了前几行。
I only read 了 first/front few lines
I only read the first few lines.
他走前把门关上了。
he go before 把 door close up
He closed the door behind him.
前不久
before not long
not long ago
就在圣诞节前
just in Christmas before
just before Christmas
在后的, 将要在前。在前的, 将要在后。
So the last will be first, and the first will be last. (Matthew 20:16)
I suggest beginning with the Chinese Grammar Wiki's article Preposition, where there's many examples and links. In practice, I expect these terms are all called "prepositions" 介系词 (or 介词), as the distinction in terminology is unimportant (and confusing).
[To be honest, this sounds like a linguistics question with "in Chinese" tacked on. Consider asking at Linguistics.SE; they might be more familiar with the nuances, and able to give better answers.]
Postpositions
Judging from Wikipedia's examples, a "postposition" 后置词 (as opposed to "preposition" 前置词) in Chinese is where direction ("position") is indicated directly after a noun, and not before. For example:
图书馆里 (in the library)
零下 (below zero)
二战前 (before World War II)
是我的 ([it] is mine)
In the last example, the possessive particle 的 turns 我 = "me" into 我的 = "mine".
Circumpositions
Chinese also has "circumpositions", particularly in conjunction with 在 to express location. Here, direction ("position") is indicated both before and after a noun.
我站在桌子上 (I stand on the table)
宝宝在我肚子里 ([the] baby [is] in my tummy)
我从北京来 (I come from Beijing)
Prepositions
Here, direction ("position") is indicated before a noun, and not after.
跟我去 (go with me)
对我说谎 (lie to me)