A shoe is an item of footwear. Shoes may vary from a simple flip-flop to a complex boot. Shoes may have high or low heels, although in western cultures, high heels are considered a women’s style. Shoe materials include leather or canvas. Athletic shoe soles may sometimes be made of rubber.
The earliest known shoes date from about 8000 to 7000 BCE and were found in Oregon, USA in 1938[1]. However, the materials used for making shoes do not normally last for thousands of years, so shoes were probably in use long before this. Physical anthropologist Erik Trinkaus believes he has found evidence that the use of shoes began in the period between about 40,000 and 26,000 years ago, based on the fact that the thickness of the bones of the toes (other than the big toe) decreased during this period, on the premise that going barefoot results in greater bone growth before this period.[1]
The insole is the interior bottom of a shoe, which sits directly beneath the foot. Many shoes have removable and replaceable insoles, and extra insoles are often added for comfort or health reasons (to control the shape, moisture, or smell of the shoe).
The outsole is the layer in direct contact with the ground. Dress shoes have leather outsoles; casual or work-oriented shoes have outsoles made of natural rubber or a synthetic imitation. The outsole may comprise a single piece, or may comprise separate pieces of different materials. Often the heel of the sole is rubber for durability and traction, while the front is leather for style. Specialized shoes will often have modifications on this design: athletic cleats have spikes embedded in the outsole to grip the ground; many kinds of dancing shoes have much softer or harder soles.
The layer in between the outsole and the insole that is typically there for shock absorption. Some types of shoes, like running shoes, have another material for shock absorption, usually beneath the heel where one puts the most pressure down. Different companies use different materials for the midsoles of their shoes. Some shoes may not have a midsole at all.
Dress shoes are categorized by smooth and supple leather uppers, leather soles, and narrow sleek figure. Casual shoes are characterized by sturdy leather uppers, non-leather outsoles, and wide profile.
Some designs of dress shoes can be worn by either gender. The majority of dress shoes have an upper covering, commonly made of leather, enclosing most of the lower foot, but not covering the ankles. This upper part of the shoe is often made without apertures or openings, but may also be made with openings or even itself consist of a series of straps, e.g. an open toe featured in women’s shoes. Shoes with uppers made high to cover the ankles are also available; a shoe with the upper rising above the ankle is usually considered a boot but certain styles may be referred to as high-topped shoes or high-tops. Usually, a high-topped shoe is secured by laces or zippers, although some styles have elastic inserts to ease slipping the shoe on.
