What Does Target Disk Mode (TDM) Mean?
Target Disk Mode (TDM) is a special boot utility available only for Macintosh computers. Any Macintosh computer booted in Target Disk Mode can be connected to the port of any other computer (Mac or PC), with the Macintosh computer acting as an external device.
Target Disk Mode is also known as Target Mode.
Techopedia Explains Target Disk Mode (TDM)
Target Disk Mode can help users in sharing files between two computers which are connected by FireWire, Thunderbolt, USB or Ethernet ports. When the “T” key is is pressed during power-up of a Macintosh that supports Target Disk Mode, the operating system does not boot; rather, the firmware in the device enables the device to act as an external mass storage device which can be connected to other devices.
There are many advantages associated with Target Disk Mode. Some Macintosh computers allow their CD drives or other internal or external peripherals to become available for use to the host computer. Target Disk Mode is also helpful with high transfer speeds, data retrieval or when the display of one of the computer is not functioning. It is also a popular technique transferring data between two computers, and also for troubleshooting malfunctioning Macintoshes.