Computer Hardware

Pixel

Definition

A pixel is the smallest controllable element of a picture represented on the screen. It is a single point in a raster image, or a "picture element".

Why It Matters

All digital images, from photos to the icons on your desktop, are composed of a grid of pixels. The total number of pixels determines the image's resolution and level of detail.

Contextual Example

A monitor with a 1920x1080 resolution is a grid of 1,920 pixels horizontally and 1,080 pixels vertically, for a total of over 2 million individual pixels. Each pixel can be set to a specific color to form the final image.

Common Misunderstandings

  • Pixel density, measured in Pixels Per Inch (PPI), describes how closely packed the pixels are. A higher PPI results in a sharper, more "Retina"-like display.
  • A "dead pixel" is a pixel that is stuck on a single color or is always off.

Related Terms

Last Updated: December 17, 2025