The IBM 3380 Direct Access Storage Device was introduced in June 1980.
IBM uses many terms to describe its various magnetic disk drives, such as direct access storage device, disk file and diskette file.
The product, called Iceberg, uses DASD, or direct access storage device technology to quickly store and recall data from a number of disk drives.
In the 1970s IBM introduced the Direct Access Storage Device ( DASD ) with fixed-block architecture using sizes of 512, 1024, 2048, or 4096 bytes.
IBM introduced the IBM 3310 Direct Access Storage Device on January 30, 1979 for VM, the only S / 370 operating systems that supports FBA devices.
The IBM 3390 Direct Access Storage Device series was introduced November 1989, offering a maximum storage of up to 22 gigabytes in a string of multiple drives.
Although its storage medium was tape, the 2321 was a direct access storage device which could directly access a record rather than scan all the tape to find a record as would a conventional tape drive.
In mainframe computing a "'PR / SM "'( "'Processor Resource / System Manager "') is a type-1 Hypervisor ( a virtual machine monitor ) that allows multiple I / O channels and direct access storage devices ( DASD ).
When direct access storage devices became available, programming languages added ways for programs to randomly access records one at a time, such as access by the values of key fields or by the position of a record in a file.
Beginning with its 1964 System / 360 announcement IBM's mainframes initially accessed CKD ( Count key data ) subsystems via a channel connected to separate Storage Control Units ( SCUs ) with attached Direct Access Storage Devices ( DASD ), typically a hard disk drive.