Abstract: Write-read unit in the form of a compact hybrid drive for combination or alternative use of plugable, removable, encapsulated flat modules equipped with semiconductors (IC cards) and with one or several drives for rotating storage media, such as drives for floppy disks, hard disks, compact disks as well as magneto-optic drives to be connected to electronic devices, such as electronic data processing machines, printers or controls. The selection of the write-read unit is effected via an integrated electronics either joint or separate for the storage media. Existing electronic devices can be extended without requiring additional space in order to shift complex data processing transactions onto the IC card, thus relieving the central processing unit.