In footwear and fashion, flip-flops (also known as thongs, jandals, slippers, or pluggers) are a flat, backless, usually rubber sandal consisting of a flat sole held loosely on the foot by a Y-shaped strap, like a thin thong, that passes between the first (big) and second toes and around either side of the foot. They appear to have been developed based on traditional Japanese woven or wooden soled sandals.
The flip-flop is not the only type of thong sandal. Other types exist, many of which are dressier and more formal than simple flip-flops. A basic thong sandal is held on the foot by a strip that fits between the first and second toes and is connected to a strap usually passing over the top or around the sides of the foot. Some thong sandals have a strap that forms a loop around the first (big) toe. However, many different additions and variations of straps are possible. Thong sandals come in a variety of styles such as women's heels, slides, and wedges, or kitten heels.
Flip-flops have a style of their own, different from other types of shoes. These dressier versions of the thong sandal are often made of leather, suede, patent leather, metallic finishes, fabric and other textiles. Based upon prevailing fashion, they are sometimes embellished with buckles, jewelry, fringes, medallions and beading. In their more formal incarnations, thong sandals are interchangeable with any other dressy sandal, and are often worn as dress shoes. The term "flip-flop" is not generically used to describe this dressier style of thong sandal.
Because of the popularity of thong sandals as dress shoes, hosiery manufacturers make hose (stockings) with a gap between the first toe and second toes to accommodate the thong.
In most developing countries, rubber flip-flops are the cheapest footwear available – typically less than $1, and many measures are used to reduce cost, such as making them out of recycled tires . Because of this, they are very widely used in these countries as typical footwear instead of a fashion statement. Despite their disposable design, street vendors will repair worn sandals for a small fee.
Flip-flops are very economic shoes not just in developing countries, but also in countries such as the US. They are generally very cheap, and made to be disposable. The strap between the toes can snap very easily after moderate use, but this problem was somewhat alleviated with the invention of replacement straps that could be "snapped" back into place on a shoe. Still, the average life expectancy of a pair is perhaps only a year or so, not counting the strap, depending on the material make-up of the soles.
Flip flops are also popular with barefooters when they have to wear shoes since they allow the foot to be out in the open but still constitute a shoe, and can be quickly and easily removed. They are also popular because they are easy to carry.
On July 19, 2005, some members of Northwestern University's national champion women's lacrosse team were criticized for wearing "flip-flops" to the White House to meet with President George W. Bush. Although the women pointed out that their shoes were not "beach shoes," but were dressier thong sandals, many weighed in on this fashion choice. Those adding to the controversy included Meghan Cleary, a footwear expert, who stated that a closed-toe shoe would have been more appropriate. Cleary noted on MSNBC's Connected: Coast to Coast program as saying the flip-flop flap indicated a cultural shift similar to when blue jeans were first worn in public. The Northwestern Women's Lacrosse Team auctioned off the thong sandals worn to the White House to raise money for a 10 year-old girl with a brain tumor.
In Japan and Korea, where it is common to leave shoes outside the house and the use of squat toilets is common, flip-flops are typically provided to wear while using the toilet.
The use of flip-flops has also been encouraged in some branches of European and North American military as sanitary footwear in communal showers, where wearing flip-flops slows the spread of fungal infections. Following on from this, some soldiers and other trampers or hikers have begun carrying flip-flops, or a pair of flip-flop soles sewn to socks, as a lightweight emergency replacement for damaged boots.
The Indian manifestation of the flip-flop, the chappal, has even been known to be deployed as a weapon, both as a truncheon and a missile, although it is more commonly merely a threat. It is not unheard of for people to whip off their chappals in the heat of an argument, in order to make their aggravation more palpable to the other party. (Touching the shoes or feet of another, in some Indian cultures, is a sign of respect or submission).
The modern design was purportedly invented in Auckland, New Zealand by Morris Yock in the 50's and patented in 1957. However, this claim has recently been contested by the children of John Cowie. John Cowie was an England-raised businessman who started a plastics manufacturing business in Hong Kong after the war. His children claim that it was Cowie that started manufacturing a plastic version of the sandals in the late 1940s and that Morris Yock was just a New Zealand importer. His children say that their father claimed to have invented the name Jandal from a shortened form of 'Japanese Sandal'. John Cowie and family emigrated to New Zealand in 1959.
Despite 'jandal' being commonly used in New Zealand to describe any manufacturer's brand, the word Jandal is actually a trademark since 1957, for a long time owned by the Skellerup company.
In countries other than New Zealand, jandals are known by other names. For example, thongs, in Australia, where the first pair were manufactured by Skellerup rival Dunlop in 1960 and became popular there after being worn by the Australian Olympic swimming team at the Melbourne Olympic Games in 1956. In the UK and US they are most commonly known as flip-flops. Thongs may have been familiar in the United States in the mid-19th century. An 1861 letter to the editor of The New York Times mentioned poorly equipped troops in the Seventh Regiment Volunteers wearing "flip-flaps": "The men were not in uniform, but very poorly dressed, — in many cases with flip-flap shoes. The business-like air with which they marched rapidly through the deep mud of the Third-avenue was the more remarkable." Later the letter reads: "The men have not yet been supplied with shoes, and yet still march flip-flop. Why? The letter does not describe the men's shoes in detail, so it is not clear whether it is referring to footwear of the flip-flop style, or perhaps to the poor state of their shoes.
Thongs now come in a variety of shoe styles other than the traditional flat sandal, such as women's heels, slides, and wedges.
The shoes gained popularity as celebrities started wearing them and high end designers started producing them. Designer Sigerson Morrison added a kitten heel to flip flops.
"Flip flop" is a trademark protected brand-name in Germany, owned by flip*flop GmbH and the Bernd Hummel Group.
While widely regarded to be comfortable, thongs do not provide ankle support, and can cause many foot-related problems. Dr. John E. Mancuso, a podiatrist at the Manhattan Podiatry Associates in New York, has pointed out that some thongs have a spongy sole, so when the foot hits the ground, it rolls inward and the sponge allows it to roll even more than usual. This is known as pronation and causes many problems in the foot. Each time a foot hits the ground, the arch is supposed to be locked to absorb shock. But during pronation, the arch opens and releases this locking mechanism, leading to problems such as pain in the heel, the arch, the toes and in the forefoot. Overpronation of the foot also results in flat feet, especially if flip flops are worn throughout childhood and adolesence when the muscles, bones, and tendons of the feet are growing and developing. Exacerbating this, some flip-flops force a person to overuse the tendons in the foot, which can cause tendinitis.
Many people believe that the pronation of the foot is meant to be left uncontrolled. The arch is supposed to flex downward to absorb shock, rather than the arch being locked. This is proven only by a degree of neutral runners as it can be contradicted that over or under-pronation can lead to more health problems other than strengthening the foot.
Ankle sprains are also common due to stepping off a curb or stepping wrong; the ankle bends, but the flip flop neither holds on to nor supports it. The open nature of flip-flops also makes the wearer more susceptible to stubbed toes, and exposes the foot to the environment. The toe grip can be useful for preventing the foot from slipping forward in a convenient sandal, but flip flops with bands across higher areas of the foot or the arch are recommended for support and keeping the shoe on the foot. Thong sandals are also popular with the same proportions and structures of flip flops, but with the addition of a slingback or an ankle strap that holds and supports the foot in a stable position. Arch support is also found in many more expensive and better made flip flops rather than the ubiquitous foam materials. Spending more on a better quality, better created shoe can influence the wearer's health and safety. Such shoes are also more commonly endowed with rubberized soles and better cushions.
In 2008, Auburn University researchers found that wearing thong-style flip-flops can result in sore feet, ankles and legs. The research team, who presented their findings at the annual meeting of the American College of Sports Medicine in 2008, found that flip-flop wearers took shorter steps and that their heels hit the ground with less vertical force than when the same walkers wore athletic shoes. When wearing flip-flops, the study participants did not bring their toes up as much during the leg’s swing phase, resulting in a larger ankle angle and shorter stride length, possibly because they tended to grip the flip-flops with their toes. This repeated motion can result in problems from the foot up into the hips.
Some people have also noted that after prolonged wearing of flip-flops they get 'Phantom Flip-Flop Foot' where the muscles between the toes that hold the 'thong' element in place continue to feel as though the flip-flop is in position even thouh the wearer has removed them.
One cannot wear conventional socks with flip-flops, due to the thong interfering with the sock, but in Japan tabi are a traditional sock with a slot for the thong, and toe socks (with separate compartments for each toe) also mate with flip-flops.