Heads-up display/Legends

"What you've got here, boy, is a sophisticated sensor-driven target system. It tells you when you're at the proper firing angle by glowing green. Me, I find if I'm not ready to fire when the target is lined up, this green light isn't going to help much, but some of you younger pilots seem to like it."

- Captain Trox

A Heads-up display (HUD) was a viewscreen projection that functioned as a combat aid.

Characteristics
Starfighters and other combat spacecraft were usually equipped with a HUD, located on the cockpit window. It consisted of a targeting reticle beneath an Outside Threat Indicator Array (OTIA), which notified pilots of successful laser or warhead locks made on other craft, or made by enemy craft on themselves, respectively.

HUDs were also sometimes installed in helmets to assist warriors or bounty hunters. The visors of Mandalorian helmets and clone commando helmets contained HUDs that provided information to the user and were capable of searching databases or uploading maps. The clones became somewhat dependent on the information the HUD gave them, and often felt handicapped when their helmets were off.

Specifically, Boba Fett's helmet contained a very advanced HUD, which featured information on the surrounding environment as well as a 360-degree field of vision. In addition, an advanced radar allowed his HUD to provide information on nearby rooms, and could be used to scan the HoloNet and connect with databases, allowing him to perform tasks which would normally require a computer terminal, such as trading on the stock market and buying real estate, from anywhere that was accessible through the HoloNet.