Basic digital image data is a stream of numbers, representing pixel colors
1 239 120 1 1 37 94 8 92 31 80 92 134 89 2 3 50 9 3 10 93 109 134 ...
Important additional information is:
Total memory needed for a simple image:
width * height * components * bytes_per_component
e.g. a 512x512, RGB, 8-bit image requires 768 kilobytes