The International Standard Serial Number, or ISSN, is an eight-digit code used to uniquely identify serial publications, such as magazines, journals, and newspapers. This number helps libraries, publishers, and readers easily locate and reference specific serials, ensuring accurate citation and efficient cataloging. Each ISSN is assigned to a specific title and remains the same even if the publication changes its format or frequency. The code is essential for managing subscriptions and tracking the distribution of serials in the global publishing industry, facilitating better access to information for researchers and the public.