Card catalog ID Crossword Clue

Today's (2 August 2017) crossword provided to us by New York Times and the clue is "Card catalog ID".
The right answer or rather the best answer listed below:

Understanding Today's Crossword Puzzle

Today's clue "Card catalog ID" corresponds to the answer "ISBN." The connection between the clue and the answer lies in the following points:

1. Identification: The term "Card catalog ID" suggests a unique identifier used for organizing and locating specific items. In the context of libraries, card catalogs historically contained information about various books, each assigned a distinct code for easy retrieval.
2. ISBN: The answer "ISBN" stands for International Standard Book Number, which serves as a unique identifier for individual books or publications. It functions similarly to a catalog ID in helping to differentiate one book from another in a systematic manner.
3. Library Use: Both the clue and the answer are linked to the realm of libraries and bibliographic organization. While "Card catalog ID" points towards the pre-digital era method of cataloging books, "ISBN" represents a modern standardized system for book identification.

Therefore, the answer "ISBN" aligns perfectly with the clue "Card catalog ID" due to their shared concept of unique identifiers for books, indicating a clear and logical connection in today's crossword puzzle.

Definition of "ISBN"

international standard book number, a ten-digit number assigned to every book before publication, recording such details as language, provenance, and publisher.

 The Crossword clue "Card catalog ID" published 2 time/s & has 1 answer/s. 

Crossword	Date	Answer
New York Times	2 August 2017	ISBN
L.A. Times Daily	14 December 2016	ISBN