The Library Stores Knoweldge. It creates the resource "Library" that is used to store Knoweldge. For Example if you got 1 "point" of the Library resource you get 1000 (Ratio of 1:1000) knoweldge that you can use to research more Techs.
The library points also apear to generate state culture (1 library point = 1 state culture)
Resource : 
| Library | |||
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