The HUD of an endoskeleton-based Terminator
Terminator visual displays and HUD's are usually monochromatic. T-800's, T-850's, and T-888's all have a largely red HUD, while the T-X has a blue HUD with blue/white, red, and black lettering. As shown from the T-850 PoV in Terminator 3: Rise of the Machines, the HUD of a Terminator under the influence of the T-X had its HUD changed to the blue T-X version, with the struggle for program dominance "shown" internally by switching back and forth between the default and intruder colors. The color of the PoV HUD does NOT indicate the color of the Terminator's unshielded (not flesh covered) eyes as seen from the outside.
Cameron Phillips, a Terminator of unknown series, has a full color visual display and HUD capable of switching through several modes of display, including deep thermal scan.
For both Cameron, and other Series 888 Terminators, such as Vick Chamberlain, the HUD is displayed while fully functional. When the CPU is not fully online, as when during the course of a reboot from massive damage or when a CPU's contents are being reviewed in a low-power setting, there is no HUD present, and all visual records are presented in a grainy, raw-video format. This differs from an active Terminator's access of stored video files for analysis.
However, the HUD is definitely a function of the operating system hardwired into the CPU, as demonstrated when John Connor's own computer and webcam begins displaying the Terminator HUD after the CPU is given too much power, and the unit seizes control of the equipment it is plugged into.
The HUD Genesis
The HUD and the Series 1000
- The Terminator
- Terminator 2: Judgment Day
- Terminator 3: Rise of the Machines
- Terminator :The Sarah Conor Chronicles
- Terminator Salvation
- The term "head-up display" (or HUD) is never actually used in the Terminator movies or TV shows. It is a widely used military term, originally used for military aviation.
- It is unclear why a Terminator would visually display decision options on their HUD. Displaying data visually takes much more CPU (and time) than evaluating data within memory, so this would significantly slow down the decision making process of Terminators.
- Displaying decision options on the HUD (e.g. "Evade" or "Terminate") does allow the audience into the mind of the Terminator without requiring them to speak. This is probably the true reason this is done: to communicate with the audience, rather than being a practical method of decision making by Terminators.
- Alternatively, the HUDs could have been designed by the original human engineers involved with Terminator technology. This would explain why the HUDs have so many visual indicators for data, as well as so many examples of human interface design (e.g. icons, menus). These sorts of interface cues are rarely if ever used in typical machine/machine interaction.
- The T-800 HUD from The Terminator showed MOS Technology 6502 assembly code on two occasions: specifically, the assembly code was for the Apple-II and was taken from Nibble Magazine. 
- ↑ Cameron's video playback in "Samson & Delilah"
- ↑ "Vick's Chip"
- ↑ A delete scene of pilot episode from Season 1 DVD, where Cromartie reboots, then plays back video of the truck that struck him in order to target and track it by identification of the license plate.
- ↑ "It is well-known that in two instances, there is 6502 assembly code on the T-800’s HUD, and many sites have analyzed the contents: It's Apple-II code taken from Nibble Magazine." http://www.pagetable.com/?p=64