early animations were created from series of single images with minor changes from one
image to the next; rapidly moving from one to the next could simulate motion to the human eye
early computer animations worked on the same principle, except that computers were able to
generate the images algorithmically.
computers became able to perform calculations to generate visual representations so
rapidly that the changes needed to be slowed down so that the animation effects were perceptible
thanks to the rise of the video game industry, there have been significant and rapid developments
in the code solutions available for animation.
today, there are lots of tools built in to high level languages like JavaScript/jQuery for animation: