Hammerspace

Hammerspace (also known as malletspace) is a fan-envisioned extradimensional, instantly accessible storage area in fiction, which is used to explain how animated, comic, and game characters can produce objects out of thin air.

This phenomenon has existed in animation for years, dating back to early Warner Bros.' Looney Tunes/Merrie Melodies animated cartoons.

The phenomenon which later became known as "Hammerspace" has been occurring in animation for many years. Inexplicable production of items dates back to the very beginning of animated shorts and was a fairly common occurrence during the golden age of animation. Warner Bros. cartoon characters are particularly well known for often pulling all sorts of things—guns, disguises, matches, bombs, anvils, mallets—from behind their backs or just offscreen. However, this phenomenon was mostly just left to suspension of disbelief. Only recently have fans created a pseudo-explanation to explain (albeit jokingly) the phenomenon.

The term "Hammerspace" itself originates from a gag common in certain anime and manga. A typical example would be when a male character would anger or otherwise offend a female character, who would proceed to produce, out of thin air, an oversized wooden rice mallet (okine) and hit him on the head with it in an exaggerated manner. The strike would be purely for comic effect, and would not have any long-lasting effects. The term was largely popularized first by fans of Urusei Yatsura, and later of Ranma ½. It is believed by some that the term "Hammerspace" itself was coined after Ranma ½'s character Akane Tendo due to the fan perception that she has a tendency to produce large hammers from nowhere. In the original manga she much more frequently uses her fists and/or objects that were pictured in the nearby scenery. The anime makes more use of hammers as a comedic tool, however.

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