The Thaumatrope

The Thaumatrope is regarded as one of the earliest examples of what we would call animation.

Whilst it may not follow the usual perceived notion of actually animating drawn objects or characters, it makes use of a phenomenon or optical illusion known as 'Persistance of Vision' - The human brains ability to remember an image for a split second making it appear to blend into the next proceeding image.

https://en.wikipedia.org/wiki/Persistence_of_vision

Whilst there is some uncertainty in regards to the actual time period it was invented, it is generally accepted that it was made popular by Dr Paris, M.D. Cantab. FRS who is credited as being the first to take the Thaumatrope commercial. Certain historical  researchers have found several examples of thaumatropes being used years before Dr Paris, with some finding evidence In his 1864 memoirs of mathematician Charles Babbage (1791-1871) having made a one off thaumatrope with a coin when challenged with a brainteaser at a dinner party.

The challenge? to see if there was a way to show both sides of a coin at the same time.

http://www.stephenherbert.co.uk/thaumatropeTEXT1.htm

It's concept was simple, a two sided circular card would have a different but related images on each side. The card would be suspended by two bits of string or elastic and twisted to make the card spin causing the two images to appear to blur or bend together.

Some advantages:

It was very cheap to make and easy to operate

It helped kick start the whole concept of animation.

The simple concept still holds up and works today

Some disadvantages:

Limited to two frames

Did not actually animate objects.