The lack of support provided by thong sandals is thought by some to be a major cause of injuries.
As they became more popular, some people started wearing them for dressier or more formal occasions.
High-end flip-flops made of leather or sophisticated synthetic materials are commonly worn in place of sneakers or loafers as the standard, everyday article of casual footwear, particularly among teenagers and young adults, although it is not unusual to see older people wearing playful, thick-soled flip-flops in brilliant colors.
The modern sandals are made of more modern materials, such as rubber, foam, plastic, leather, suede, and even fabric.
While flip-flops do provide the wearer with some mild protection from hazards on the ground, such as hot sand at the beach, glass, thumb tacks or even fungi and wart-causing viruses in locker rooms or community pools, their simple design is responsible for a host of other injuries of the foot and lower leg.
Most modern flip-flops are inexpensive, costing as little as $5, or less in some parts of the world.