rear-projection TV: RPTV. A type of projection system in a home theater in which both parts of the front projector (the projector and the screen) are housed in a single box. The projector illuminates the back of the screen instead of the front.

receiver: A/V receiver. A device that controls your home theater by selecting audio/video sources, decoding surround-sound formats, amplifying sound, and tuning in radio programming.

resolution: A measure of the precision and sharpness of a video display's picture, based on the pixels or lines of resolution available on the screen. For HDTVs, display vendors typically focus on the vertical lines of resolution, usually 720 or 1080.

RG6: A type of coaxial long-run cable that you can use to connect your home theater to the rest of your house.

RPTV: Rear-projection TV.

RS-232: Short for Recommended Standard 232. RS-232 is more commonly known as a serial connection. You might use this type of connection between a modem and an older PC. USB has replaced most RS-232 connections.