paper folding

Art of folding objects out of paper without cutting, pasting, or decorating. Its early history is unknown, but it seems to have developed from the older art of folding cloth. Origami has reached its greatest development in Japan, with hundreds of traditional folds and an extensive literature dealing with the art. There are two types of Japanese folds: figures used in ceremonial etiquette, and objects such as animals, flowers, furniture, and human figures. Some objects have amusing action features; best known is the bird that flaps its wings when its tail is pulled. Paper folding has also flourished in Spain, South America, and Germany.

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In geology, an undulation or wave in the stratified rocks of the Earth's crust. Stratified rocks were originally formed from sediments that were deposited in flat, horizontal sheets, although in some places the strata are no longer horizontal but have warped. The warping may be so gentle that the inclination of the strata is barely perceptible, or it may be so pronounced that the strata of the two flanks are essentially parallel or nearly flat. Folds vary widely in size; the tops of large folds are commonly eroded away on the Earth's surface.

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• Above the fold, a graphic design concept originating in newspapers
• Fold (from the Saxon "falod") meaning a staked-off pasture area (e.g. Sheepfold, an enclosure for sheep) and used in place names such as the Fold Villages.
• Catastrophe theory#Fold catastrophe, one of the most basic objects in singularity theory.
• -fold, a suffix added to a cardinal number signifying "multiplied by"
• skin fold
• In computing:
• Fold (higher-order function), a family of higher-order functions in functional computer programming
• Fold (Unix), a program in the GNU Core Utilities

Fold or folding may refer to:

• folding, in poker, the act of withdrawing from a hand rather than meeting the bet
• Paper folding (see also below under Mathematics)
• origami, the art of paper folding
• pattern welding, the folding of metal
• bankruptcy
• Folding in cooking refers to a gentle mixing technique, somewhere between a cutting motion and a stirring motion, used to incorporate ingredients into a batter or other mixture, such as for a cake.
• Folding (Book folding) in the publishing process refers to the folding of the pages of the book, after printing and before binding
• In science:
• fold (geology)
• in computer programming:
• case folding is a term denoting the conversion of all characters in a string to lower- or upper-case
• code or text folding (as in a folding editor for folding code or text)
• In functional languages folding refers to processing some data structure and accumulating a result.
• Mathematics of paper folding
• folding (chemistry) or intramolecular self-assembly of molecules to assume a specific shape
• protein folding
• Folding@home, a distributed computing project designed to perform computationally intensive simulations of protein folding and other molecular dynamics.
• Aliasing#Folding, as used in signal processing

See also

• folder
• bifold door