an animated GIF with 5 frames where the rectangle marks the active frame

Animation is creating an illusion of movement by quickly switching between different still images, which are called frames.

In the example here, Motion Blur was applied to visually hint at the path of movement. This is often used in animations with a low frame count to make the movement appear smoother without adding extra frames.

In pixel art, animations are usually shared in the form of a GIF file.

further reading:

• Animation