A Pixel is the smallest element of an image.

Each pixel corresponds to one value at that point. In an 8-bit grayscale image, the value of the pixel is between 0 and 255.

The value of a pixel at any point corresponds to the intensity of the light photons striking at that point.

Each pixel stores a value proportional to the light intensity at that particular location.

A pixel is also known as PEL.

Total number of pixels = Number of rows * Number of columns

The number of (x,y) coordinate pairs also make up the total number of pixels.