A stiletto heel, or just stiletto, is a shoe with a long, thin, high heel. The term stiletto – an Italian word for a thin blade – originally referred to just a slender heel but came to identify a high-heeled shoe as a whole.

Stiletto heels may vary in length from 2.5 centimetres (1 inch) to 25 cm (10 inches) or more. All high heels counter the natural functionality of the foot, sometimes causing skeletal and muscular problems if users wear them excessively. Despite their impracticality they persist as a fashion option.

The stiletto heel came with the advent of technology using a supporting metal shaft or stem embedded into the heel, instead of wood or other, weaker materials that required a wide heel. Italian shoe designer Salvatore Ferragamo paved the way for stilettos by inventing the steel arch.

Stiletto heels concentrate a large amount of force into a small area. The great pressure under such a heel can cause damage to carpets and floors. The stiletto heel, unless equipped with a "heel stopper" to enlarge the floor contact area, can be impractical for outdoor wear on soft ground (such as grass, sand or mud), or in environments where floor damage is unacceptable.

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