50 Fun Facts About Origami

The word origami combines two Japanese words meaning what?

Ori comes from the verb oru, to fold; kami means paper.

What is generally regarded as the best-known origami model?

Modern practitioners discourage cuts, glue and markings on the paper.

Origami folders use which Japanese term for designs that involve cutting the paper?

Cutting was common in traditional Japanese folding but fell out of the modern repertoire in the 1960s and 70s.

What is the modern goal of origami, according to its usual definition?

Traditional Edo-period folding was less strict, sometimes using cuts and non-square sheets.

Folding a thousand paper cranes, senbazuru, is said to grant the folder what?

The number matches the thousand years the crane was said to live.

Sadako Sasaki, the Hiroshima girl who folded cranes while dying of leukaemia, died in which year?

She was 12; a statue of her holding a golden crane was unveiled in the Hiroshima Peace Memorial Park in 1958.

In the popular version of Sadako's story, how many cranes had she folded before her death, her friends completing the rest?

Her family says she actually folded more than a thousand; the story is dramatised worldwide.

Which US president presented two hand-folded paper cranes to the Hiroshima Peace Memorial Museum in 2016?

In Japanese culture the crane's wings are believed to carry souls to paradise.

Who is considered the grandmaster of modern origami, credited with the standard diagram symbols and inspiring a renaissance of the art?

He founded the International Origami Centre in Tokyo in 1954, the year his first monograph appeared.

By his own 1989 estimate, roughly how many models had the grandmaster of origami created?

Only a few hundred appeared as diagrams in his 18 books.

Emperor Hirohito awarded the grandmaster of origami which honour in 1983?

He was born and died on 14 March, exactly 94 years apart.

In the Yoshizawa-Randlett diagramming system, what does a dashed line indicate?

Samuel Randlett and Robert Harbin added symbols like "rotate" and "zoom in" and adopted it as the standard in 1961.

What is a wet-folded model's advantage over one folded dry?

The paper is wiped with a damp cloth, moulded, and holds its shape when it dries; heavier papers of 100 g/m2 or more suit it best.

The oldest known technical book on recreational origami, Hiden senbazuru orikata, was published in which year?

Its 49 pieces were created by a Buddhist monk named Gidō in Ise Province.

The 1747 book Ranma zushiki, which included paper cranes, was a collection of designs for what?

It also contains the first historical evidence of a modular origami design.

Which German educator's kindergarten system, imported by Japan in the 1860s, brought the ban on cuts and the two-coloured starting sheet?

Japan's first kindergarten opened in 1875 and its 1877 regulations listed origami among 25 activities.

Historian Joan Sallas attributes the decline of Europe's elaborate napkin-folding tradition to the arrival of what?

Porcelain replaced complex napkin folds as a dinner-table status symbol among the nobility.

The stylised bird known as the pajarita is an early example of paper folding from which country's tradition?

In Spain recreational folding is called papiroflexia; in China it is zhe zhi and in Korea jongi jeobgi.

What is the traditional Japanese paper used for origami, made from gampi, mitsumata or paper mulberry fibres?

It is tougher than wood-pulp paper and is registered as UNESCO intangible cultural heritage.

Ordinary pre-packaged origami squares, coloured on one side and white on the other, are known simply by the Japanese word for paper. What is it?

The word simply means paper in Japanese; standard squares include 75 mm, 6 inch and 10 inch.

Decorative modular folding balls, whose name means "medicine ball", are known as what?

The word means medicine ball; the pieces may be held together with thread or glue.

The style of assembling large numbers of folded units, often called "3D origami", is also named Golden Venture folding after what?

Chinese refugees who arrived on the Golden Venture developed it while detained in America.

Modular origami was re-invented in the 1960s by Robert Neale in the US and later by which Japanese folder, whose unit bears his name?

The Sonobe unit is the classic building block of modular polyhedra.

Pureland origami, developed by John Smith in the 1970s, restricts folders to what?

It was designed to help inexperienced folders and people with limited motor skills.

Which folder was the first to explore twist-fold tessellations systematically, in the 1960s?

Chris Palmer later folded tessellations in silk after seeing the Zilij patterns of the Alhambra.

The first international convention devoted to origami tessellations was held in 2006 in which city?

Eric Gjerde published the first instruction book on tessellation folding in 2008.

Teabag folding, using small wrappers with symmetrical designs, was developed in 1992 by an artist from which country?

Tiny van der Plas devised it to embellish greeting cards; the basic rosette needs eight kite-folded squares.

The rigid Miura fold has been used to deploy what from a folded position in space?

Japan's 1996 Space Flyer Unit deployed a 2D array from a Miura-folded configuration.

Origami principles have been applied to the deployment of which two medical and automotive devices?

Both must unfold from a compact form reliably.

Origami can construct which two classical problems impossible with compass and straightedge?

The sixth Huzita-Hatori axiom, based on Margherita Beloch's 1936 fold, lets origami solve general cubic equations.

Maekawa's theorem states that at any vertex of a flat-folded crease pattern, the numbers of mountain and valley folds differ by how many?

Kawasaki's theorem gives the companion condition on the angles around the vertex.

Kawasaki's theorem says a single-vertex crease pattern is flat-foldable if the alternating angles sum to how many degrees?

Equivalently, adding and subtracting the consecutive angles alternately must give zero.

The seven axioms of origami construction, now named for Huzita and Hatori, were first fully stated in 1986 by which French mathematician?

His work was overlooked; Huzita rediscovered six in 1989 and Hatori the seventh in 2001.

Which physicist and origami artist wrote the TreeMaker algorithm and worked at NASA's Jet Propulsion Laboratory?

He holds 46 patents in lasers and optoelectronics and uses a laser cutter to score complex folds.

In technical origami design, the allocation of paper regions to model parts is computed by what method?

A circle encloses the most area for its perimeter, so packing circles gives maximum paper efficiency.

Which MIT professor, appointed at 20 as reportedly the youngest in the institute's history, co-proved the fold-and-cut theorem?

He won a MacArthur "genius grant" in 2003; his father Martin was a co-author.

According to an 1873 magazine article, who may have proposed five-pointed stars for the US flag because they can be made by folding and a single cut?

Harry Houdini also published fold-and-cut puzzles; the theorem was proved in 1999.

Britney Gallivan debunked the myth that paper cannot be folded in half more than eight times by folding a 1,200-metre roll of toilet paper how many times?

The California high-schooler derived the maths in December 2001 and did the folding in January 2002.

The playground paper fortune teller is also known in the US by what name?

The same shape can serve as a salt cellar or as pincers for play-catching "cooties".

Which action-origami model, the oldest, first appeared in traditional Japanese folding?

Robert Lang's instrumentalists play when their heads are pulled away from their bodies.

The 2008 documentary Between the Folds, about origami, won which honour in 2010?

Vanessa Gould directed it; it aired on Independent Lens.

Which Japanese artist, born in Niigata in 1951, is regarded as a master of modular origami boxes and medicine-ball models?

She has published in Japanese, Korean and English.

In Japan, stylised ceremonial folding, such as noshi wrappings, is called what to distinguish it from recreational origami?

Only recreational, yūgi origami is generally recognised as origami.

Paper folding first came to be used at Shinto shrines for what?

The Heian court then set etiquette codes for wrapping money and gifts in folded paper.

Origami butterflies used at Shinto weddings to represent the bride and groom date back to which era, when the Ogasawara and Ise clans codified decorum?

A 1680 poem by Ihara Saikaku describes them.

Which city in Mie Prefecture designated 49 folding methods from the oldest origami manual as Intangible Cultural Properties in 1976?

It was the monk Gidō's home town, and it certifies people who can correctly produce the works.

The Japanese papermaking technique developed around 805-809, which adds mucilage to make stronger paper, is called what?

It improved on the conventional tame-suki method after paper arrived from China via Korea.

Origami was offered as an extra activity for elementary school children in which country from 1974?

During the 1980s folders began systematically studying the mathematics of folded forms.

Strip folding, which combines folding and weaving, produces which common small model?

It is also called the Chinese lucky star or wishing star; the Moravian star, another strip fold, has 16 spikes.

Which hand tool is used to make sharp creases easily?

Paper clips can serve as extra fingers and tweezers help with tiny folds; some purists use no tools at all.