The Graphics Interchange Format (GIF) has many advantages when it comes to animation. For a long time, animated GIFs were the preferred method of animation on the Internet---especially for web banners. However, with the birth of other graphics formats and more powerful animation options, the disadvantages of GIF animation became apparent. The GIF format and GIF animation is still used on many web pages, but its limitations have reduced its use to very specific instances.
GIF Animation and Photographs
The GIF file format is not suited to handling images that have colour schemes in the millions. This makes it very difficult for a GIF to accurately reproduce a photograph, especially as new cameras with higher and higher "megapixel" resolutions are released almost daily. The GIF colour palette is limited to 256 colours and this makes animating a colour photograph an undesirable option. Through a process called "dithering," the GIF file will attempt to approximate the colours as they would be within the 256 colours that the file type is allowed. Animated GIFs that are based on photographs are "grainy" or "pixelated" and do not offer the same level of quality as other file types such as PNG or JPG.
GIF Animation and Compression
GIF animation is a frame-by-frame animation style that uses a "lossless" compression algorithm. This means that each and every pixel contained on every frame of the original image animation will be stored when the file is saved. This type of compression, while good for preserving the image quality, results in larger file sizes that increase the download time for each image.
GIF Animation and Programming
Another major disadvantage of GIF animation is the lack of programmable interactivity. A large portion of web banners with animation today offer some level of interaction by the user. GIF animation is a continuous loop that cannot be controlled in any way by the viewer. This particular aspect of GIF animation has forced many programmers to choose other options for their web animations.
Programmers also face an additional challenge when using GIF animation. Unlike other file types such as SWF, GIF animations are not editable once encoded. After a designer has chosen to save their file as a GIF animation, the actual sequence is no longer available to be changed if something doesn't work exactly as it should. While there are a number of workarounds for this problem, it is another reason to be wary of using GIF animation.