Which establishments are likely to use mainframe computers?

Mainframe computers are known for their ability to process large amounts of data quickly and efficiently, which makes them ideal for organizations that require robust computing power for extensive transaction processing and data management. An airline taking reservations operates on a system that must handle vast amounts of real-time data, such as flight schedules, seat availability, and transaction processing for reservations and ticketing. This necessitates a high level of reliability, security, and scalability that mainframe computers are designed to provide.

Other establishments, such as a small coffee shop, a local grocery store, and an independent bookstore, typically do not require the level of computing power, data management capabilities, or transaction volume that mainframes offer. These businesses often operate with less sophisticated systems, such as personal computers or smaller servers, which are more cost-effective for their needs. Therefore, it is clear why mainframe computers would primarily be utilized by large operations like airlines rather than smaller retail-oriented establishments.