S. R. Ranganathan's Five Laws of Library Science

Just a short (Wikipedia, I know) article about the 'Five Laws of Library Science' by S.R. Ranganathan. There are as follows:

1. Books are for use.
   
2. Every reader his [or her] book.
   
3. Every book its reader.
   
4. Save the time of the reader.
   
5. The library is a growing organism.
   

See also: Five Laws of Library Science, Ebook Edition by LISNews contributor AndyW.