Microtapes, also called library record tapes, library tapes, record tapes, or, more, simply tapes, were a type of computer memory storage medium used by Earth and Federation space exploration vessels from the 21st through the 23rd centuries.
In 2065, the disaster recorder of the SS Valiant was equipped with tapes. When the recorder was recovered by the USS Enterprise in 2265, both Captain Kirk and Science Officer Spock hoped that "its tapes were still intact" despite the age of the recorder and its distressed condition. Spock later commented that the tapes were burned out, but he was able to interpolate data stored in the memory banks. (TOS: "Where No Man Has Gone Before")
In addition, the sensors aboard Constitution-class vessels maintained "microtape" records. In 2267, the USS Constellation's tapes were pulled and beamed to the Enterprise for analysis of the planet killer. (TOS: "The Doomsday Machine")
Some data cards held information on specific types of foods, such as various flavors of ice cream. These could be used in conjunction with the food synthesizer to create the food listed on the tapes. In 2268, Nurse Christine Chapel passed out several of these cards to the Starnes Exploration Party orphans so they could have whichever ice cream flavor they wanted. (TOS: "And the Children Shall Lead")
A version of these tapes resembled 20th century floppy discs but with far greater capacity. (TOS: "The Cage", "The Menagerie, Part I", "The Menagerie, Part II", "Tomorrow is Yesterday", "And the Children Shall Lead", "The Lights of Zetar", "Obsession"; TAS: "The Survivor"; ENT: "In a Mirror, Darkly, Part II")