An online catalog is a digital collection of items or services that can be browsed and searched through the internet. These catalogs are commonly used by businesses, libraries, and educational institutions to showcase their products, books, or resources. Users can easily access information, including descriptions, prices, and availability, from the comfort of their own devices. Online catalogs often include features like filters and search functions, making it simple for users to find what they need quickly. They can be found on websites of retailers, such as Amazon, or in library systems, allowing patrons to explore collections without visiting in person.