The Five laws of library science is a theory proposed by S. R. Ranganathan in 1931, detailing the principles of operating a library system. Many librarians worldwide accept them as the foundations of their philosophy.

These laws are:

1. Books are for use.

2. Every reader his / her book.

3. Every book its reader.

4. Save the time of the reader.

5. The library is a growing organism.

With various tools and apps being introduced every day. Libraries are not brick and stone anymore. They serve members and non-members alike in terms of non-traditional library services; irrespective of space and time.

Looking through the library literature, one can see clearly the same Five Laws discussed, reused, or re-worded in different contexts. The American interpretation of Ranganathan’s Five Laws of Library Science as given in 1975, is as follows:

1. Books are for use. (Tapes, films, records, relic and books are for use in the information delivery system)

2. Every reader his book. (Every Reader his/ her medium)

3. Every book its reader. (To every tape, record, etc. its utility)

4. Save the time of the reader. (Save the down time of the patron)

5. Library is a growing organism.

 (A learning resources center is a growing organism) In 1992, James R. Retting devised a Sixth Law as an extension of Ranganthan’s Five Laws. The Sixth Law is “Every reader his freedom”. Jim Thompson (1992) revised Ranganathan’s Laws as follows:

1. Books are for profit.

2. Every reader his bill.

3. Every copy its reader.

4. Take the cash from the reader.

5. The library is a growing organism.

Kuronen and Pekkarinen have suggested two supplementary (6th and 7th) Laws to Ranganathan’s Five Laws:

6. Every reader his library.

7. Every writer his contribution to library.

 In 1998, Michael Gorman and Wait Crawford focused on the validity of the Five Laws and suggested five new laws as an extension of the first Five Laws. These are:

1. Libraries serve humanity.

2. Respect all forms by which knowledge is communicated.

3. Use technology intelligently to enhance services.

4. Protect free access to knowledge.

5. Honour the past and create the future.

In 2004 Alireza Noruzi applied Ranganathan’s Five Laws to the web in his paper “Application of Ranganathan Laws to the web”. They are:

1. Web resources are for use.

2. Every user his or her web resources.

3. Every web resource its user.

4. Save the time of the user.

5. The web is a growing organism .

In 2008, Carol Simpson revised these laws and applied them in the field of media They are:

1. Media are for use.

2. Every patron his information.

3. Every medium its user.

 4. Save the time of the patron.

5. The library is a growing organism.