A means of connecting a number of devices to a controller, or, used as a verb, to connect by this means. A cable is connected from the controller to the nearest of the devices and then a separate cable connects the first unit to the second and the process is repeated as required. This allows a single connector on the controller to serve a variable number of devices. It also reduces cable cost and eases installation when several devices have to be connected. The IEEE 488 and SCSI interfaces are suitable for this sort of connection.

Daisychain connection is also used as a means to prioritize I/O interrupts. In this application there is active logic at the points of interconnection to ensure that the priority accorded to a device is directly related to its place in the chain. The device nearest to the controller has highest priority.