This document provides a quick reference guide for various commands and functions across different computer reservation systems, including Amadeus, Galileo, Abacus/Sabre, and Worldspan. It outlines commands for security, information/help, encoding/decoding, scrolling, printing, availability, selling/changing/canceling flights, timetables, and adding/modifying passenger name record fields like names, phones, addresses, payments and more. The summary provides high-level overviews of the key areas covered in the document in a concise 3 sentences.