D

daisy chain

A set of devices, such as Small Computer System Interfaces (SCSIs) and Universal Serial Buses (USBs), that are connected in a series. When devices are daisychained to a microcomputer, the first device is connected to the computer, the second device is connected to the first, and so on down the line. Signals are passed through the chain from one device to the next. See also Small Computer System Interface (SCSI) and Universal Serial Bus (USB).

database management system (DBMS)

A layer of software between the physical database and the user. The DBMS manages all requests for database action from the user, including keeping track of the physical details of file locations and formats, indexing schemes, and so on. In addition, a DBMS permits centralized control of security and data integrity requirements.