What term describes the smallest unit of information within a digital image?

• A. Picture element (PIXEL)
• B. Charged-couple device (CCD)
• C. Detector element (DEL)
• D. Photostimulable phosphor (PSP)

Answer: (A)

In digital imaging, the image is built from a grid of tiny picture elements called pixels. Each pixel holds a numeric value that represents the brightness (and, in color images, color information) at that specific point in the image. The whole picture emerges from the combination of all these individual values, so the pixel is the smallest unit of information that can be stored and managed in the image data. The other terms refer to devices or components used to capture or store image data—such as a sensor that converts light to signal, a detector element within a sensor, or an imaging plate used in certain radiography systems—not the basic unit of information in the image itself.