What does CRT stand for in computer hardware?

• A. Central Radiation Tube
• B. Cathode Radiation Tube
• C. Compact Raster Tube
• D. Cathode Ray Tube

Answer: (D)

CRT stands for Cathode Ray Tube. In computer hardware this refers to the old monitor technology built as a vacuum tube. Inside, a heated cathode emits electrons, which are then accelerated toward the screen by electric fields and steered across the phosphor-coated glass to form an image. In color displays, there are separate electron guns for red, green, and blue, with a shadow mask or aperture grill to combine the colors correctly. The term emphasizes a directed beam of electrons—the cathode rays—hitting the screen. Using “radiation” would be less precise, since the device relies on a focused particle beam rather than broad, non-directed radiation. The other names aren’t standard terms for this technology, so they don’t fit the established terminology.