Abstract: Data storage units (1) for storing a plurality of individual data storage media (12), the units comprising at least one removable magazine (9, 10) in which the individual data storage media (12) can be stored within the units (1), the magazines (9, 10) being removable from the front of the units (1). At least one drive (5, 6) which reads data from or writes data to individual data storage media (12) is positioned relative to the magazine(s) (9, 10) so that the storage media (12) are fed therein and removed therefrom in a direction substantially perpendicular to the direction in which the media are removed from the magazine(s) (5, 6). A selector (20) facilitates the selective removal of media (12) from the magazines (9, 10) in which they are stored, and feeds them into the drive (5, 6), and vice versa.