In Figure 1, for example, the car appears to move quite a large distance and quite quickly. The human brain automatically interprets the blur as speed, and speed equals motion. The effect is helped along by skewing the shape of the car. The skew changes from left to right between frames 2 and 3 to suggest the difference between forward motion and a hard stop. You should take some time to explore other illustration techniques that can telegraph motion.
Cartoonists use visual shorthand all the time.
The overall dimensions of a GIF animation are determined by the size of the first frame. Banner ads, for example, are typically 468 pixels wide by 60 pixels high. For instance, in the animated-car example above, you might crop down to just enough of the image to show the new instance of the car, along with enough background to cover the car's position in the previous frame. The Layered Look Luckily, animated GIFs also support transparency, which you can exploit to further reduce the file size. The advantage of transparency in this context is that it is always treated as a single solid color, which the LZW algorithm compresses very well.