What is a pixel?

• A. A unit of information that can be only 0 or 1
• B. A tiny square or dot that contains a single point of color in a larger image
• C. A vertex in a data structure
• D. An element of a for loop

Answer: (B)

A digital image is built from tiny colored squares called pixels. Each pixel is a single point of color in the grid, and when you combine many of them, they form the picture you see. On a screen, each pixel shows a color by mixing values for red, green, and blue, and the total number of pixels (the image’s resolution) determines how much detail you can perceive. A bit, by contrast, is just a 0 or 1—the basic unit of information—while a vertex is a point in a graph or data structure, and an element of a for loop is a piece of code that repeats. So the pixel is the smallest unit that represents color in an image.