Robert Recorde invented the equal sign (=), and William Jones was the first to use the Greek letter Pi (p) to describe the world's most famous ratio.
Born in Tenby, Pembrokeshire in 1510, Robert Recorde was the foremost mathematician of 16th century Britain. Through his remarkable academic work, he virtually established the English school of mathematics and was the first to introduce algebra into this country.
Recorde is credited with developing the equal sign (=) in his book The Whetstone of Witte in 1557, although it did not gain popularity until the 1700s. He chose to use two short parallel lines in the symbol,"cause noe 2 thynges can be moare equalle."
Mathematician William Jones was born in the small village of Llanfihangel Tre Beirdd on Anglesey in 1657. In his 'Synopsis Palmariorum Matheseos' in 1706, he became the first person to use the 16th letter of the Greek alphabet to represent the ratio of the circumference of a circle to its diameter. Previously, the famous ratio, which is approximately 3.14 but cannot be calculated to perfect precision, was called the Ludolphian number, after Ludolph van Ceulen, a German mathematician. The earliest known reference to Pi occurs in a Middle Kingdom papyrus scroll, written around 1650 BC.
