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Scissors are hand-operated shearing tools. A pair of scissors consists of a pair of metal blades pivoted so that the sharpened edges slide against each other when the handles opposite to the pivot are closed. Scissors are used for cutting various thin materials, such as paper, cardboard, metal foil, cloth, rope, and wire. A large variety of scissors and shears all exist for specialized purposes. Hair-cutting shears and kitchen shears are functionally equivalent to scissors, but the larger implements tend to be called shears. Hair-cutting shears have specific blade angles ideal for cutting hair. Using the incorrect scissors to cut hair will result in increased damage or split ends, or both, by breaking the hair. Kitchen shears, also known as kitchen scissors, are intended for cutting and trimming foods such as meats.
Modern scissors are often designed ergonomically with composite thermoplastic and rubber handles which enable the user to exert either a power grip or a precision grip.
The noun scissors is treated as a plural noun, and therefore takes a plural verb. Alternatively, the tool is referred to by the singular phrase a pair of scissors. The word shears is used to describe similar instruments that are larger in size and for heavier cutting.
The earliest known scissors appeared in Mesopotamia 3,000 to 4,000 years ago. These were of the 'spring scissor' type comprising two bronze blades connected at the handles by a thin, flexible strip of curved bronze which served to hold the blades in alignment, to allow them to be squeezed together, and to pull them apart when released.
Spring scissors continued to be used in Europe until the 16th century. However, pivoted scissors of bronze or iron, in which the blades were pivoted at a point between the tips and the handles, the direct ancestor of modern scissors, were invented by the Romans around 100 AD. They entered common use in not only ancient Rome, but also China, Japan, and Korea, and the idea is still used in almost all modern scissors.