What is GIF
Graphics Interchange Format or GIF is a bitmap image format that contains a still or a moving image. Unlike JPEG, GIF uses lossless compression. Now, what is lossless compression? This means that the file will reduce the file without any loss of quality. A standard GIF can consist of 256 colors. Similar to 87a both the formats support animation by allowing a stream of images can be stored in a single file. 89a also supports animation delays. The disadvantage here that the color palette is limited to 256 colors making it a better option for color scanning rather than color photos.
The original GIF format called 87a was given by CompuServe in 1987. In 1989 the same company released another version of a GIF called the 89a version. Which supports transparent background and image metadata. Most of the GIFs use 89a version.