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In technical terms, full animation is classified as animation which has key frames, or unique drawings, for at least every other frame of footage. Animation is usually played back at about 24 frames per second. In this respect, full animation is also known as drawing "on twos" “on twos” since at least 12 frames of each second of footage are key frames2.
Hiroki Azuma's Azuma’s book Otaku: Japan's Japan’s Database Animals makes a distinction between full animation and limited animation (link) on page 113. Limited animation was developed in Japan in reaction to the realism of Disney's Disney’s animation to keep production time and costs down.
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