A call number is like a book's address; it tells you where to find a book in the library's collection. Call numbers are arranged alphabetically, and then by whole number (everything before the first period in the call number).
The following call number ranges are where you'll find most of our books on Computer Science. The Library of Congress Classification Outline provides a full guide to call numbers.
Subclass QA 75.5-76.95 - Electronic computers. Computer science
Subclass QA 76.75-76.765 - Computer software
Subclass TK 5101-6720 - Telecommunication
Subclass TK 7885-7895 - Computer engineering. Computer hardware.