Computer Animation
A series of images that create the impression that the images on screen are moving.
Key frames, tweening and interpolation
A key frame is an image created by you in your animation. To save you from having to create every stage of movement in the animation, you only need to make a key frame every so many frames. The computer works out the rest for you through a process called interpolation. The frames the computer makes are called inbetween frames - tweening.
Interpolation
Interpolation is a mathematical process.
The computer compares the frame before and after the one it is about to generate
and using maths it works out where all of the parts of the image should be.
It draws the scene in between two others.