The numerals that we use today derive, from a system used by the people of India, between the 3rd century BC and the 6th century AD. However, these numerals were described as Arabic. It reached Persia in the 9th century, then Europe, through the writings of Middle Eastern mathematicians, like Al-Khwarizmi and Al-Kindi.
In Europe, Roman numerals were still in use until the late 1500s. Fractions were adapted to the decimal system by the 16th century mathematician, Christoff Rudolff. In the early 17th century, the Scottish mathematician John Napier brought decimal points into common use. He later became known for his invention of logarithms.
The book Mercantile Arithmetic is the first to record the use of (+) and (-) sign. Robert Recorde devised the equal sign in the 16th century. The multiplication sign was first used by William Oughtred in England in 1631.
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