cylinder meaning in Information Science terminology / glossary / dictionary is:
In geometry, a regular shape with ends that are equal and parallel circles and with sides perpendicular to the ends. In sound recording, a format invented by Thomas Edison in 1877-1878 capable of storing 2-4 minutes of recorded sound (see wax cylinder). Initially used for commercial entertainment, the medium was adopted by the Dictaphone Company for use in early dictation and transcription machines.In computing, a multiplatter hard drive in which the concentric magnetic tracks on each disk platter are the same distance from the hub. Arranged in a stack, the platters are of equal size but vary in number, with high-end hard drives (normally used in servers) having as many as a dozen. Double-sided, the platters rotate at constant speed, driven by a single spindle motor (see this schematic of a multiplatter hard drive).