Quarter inch cartridge tape is a magnetic tape data storage format introduced by 3M in 1972, with derivatives still in use as of 2016. QIC comes in a rugged enclosed package of aluminum and plastic that holds two tape reels driven by a single belt in direct contact with the tape. The tape was originally 1⁄4 inch (6.35 mm) wide and anywhere from 300 to 1,500 feet long. Data is written linearly along the length of the tape in one track, or written "serpentine", one track at a time, the drive reversing direction at the end of the tape, and each track's data written in the opposite direction to its neighbor. Since its introduction, it has been widely used, and many variations exist. There is a QIC trade association that publishes QIC standards which include interfaces and logical formats. To a very large extent it was the efficiency and openness of this organization which encouraged hardware and software developers to use this type of drive and media.