Animation is the process of making the illusion of motion and the illusion of change by means of the rapid display of a sequence of images that minimally differ from each other.
Humans have probably attempted to depict motion as far back as the paleolithic period. While there were several predecessors, the 17th century invention of the magic lantern provided the first apparatus with which convincing moving images have been created. However, the movement of these images were the result of moving parts rather than a rapid succession of sequential images. The introduction of the phenakistiscope in 1833 marks the start of true animation, although it could only show loops of a limited number of "frames".
There are several examples of early sequential images that may seem similar to series of animation drawings. Most of these examples would only allow an extremely low frame rate when they are animated, resulting in short and crude animations that are not very lifelike. However, it's very unlikely that these images were intended to be somehow viewed as an animation. It is possible to imagine technology that could have been used in the periods of their creation, but no conclusive evidence in artifacts or descriptions have been found. It is sometimes argued that these early sequential images are too easily interpreted as "pre-cinema" by minds accustomed to film, comic books and other modern sequential images, while it is uncertain that the creators of these images envisioned anything like it.
Early examples of attempts to capture the phenomenon of motion into a still drawing can be found in paleolithic cave paintings, where animals are often depicted with multiple legs in superimposed positions. It has been claimed that these superimposed figures were intended for a form of animation with the flickering light of the flames of a fire or a passing torch illuminating different parts of the painted rock wall, revealing different parts of the motion.
Archaeological finds of small paleolithic discs with a hole in the middle and drawings on both sides have been claimed to be prehistoric thaumatropes that show motion when spun on a string.