The document describes the key elements of reservation systems, including:
1) The ability to check availability, offer alternatives when requested bookings are unavailable, and provide information on costs and features.
2) Recording customer details, payment methods, and providing confirmations.
3) Entering reservation details into manual or computerized systems, and generating related documentation like receipts and confirmation letters.
4) Maintaining reservations by processing changes or cancellations, following up on unconfirmed bookings, and communicating details to internal departments and external organizations.