What Animated GIF is

A type of GIF format that allows a series of static images to be displayed one after another or on top of each other, giving the effect of motion or animation. Since their implementation in Netscape Navigator 2.0, animated GIFs have been one of the easiest ways to put animation and movement on Web pages. Animated GIFs have been around since the introduction of the GIF89a format in 1989, but they didn't appear on the Web at that time because Web browsers initially did not support GIF89a's animation features.

The meaning of Vector graphics

Also called object-oriented graphics, these programs store images in the form of mathematical representations that can be resized and scaled without distortion. These "draw programs" (as opposed to paint programs) are well suited for architecture, computer-aided design, interior design, and other applications in which precision and scaling capability are more important than artistic effects. Vector graphics use computer algorithms to describe shapes, lines, animation, and so forth. The technology of vector graphics is growing in popularity because the images are scalable and smaller in file size, a plus for online viewing and downloading. Vector graphics were developed in response to the limitations of raster-based graphics (popularly known as GIF and JPG), which use pixel-by-pixel definitions and cannot be resized reliably.