GRAPHICS INTERCHANGE FORMAT
GIF files were originally meant for low quality logos and animations. They were not meant to represent high quality photographs, so their color palette is limited to 256 colors. However, GIFs can include multiple image blocks within itself.
From here, each block can contain its own 256 colors, and these blocks can be tiled together to create a cohesive image. The number of image blocks tiled within a GIF results in different file sizes. The larger number of image blocks within one GIF, the bigger the file size will be.
—- Hunter French —-