(fl. probably 1st or 2nd century AD)
Hero of Alexandria, also known as Heron of Alexandria, was a Greek mathematician and engineer who was active in Alexandria during the Roman era. He has been described as the greatest experimentalist of antiquity. He is mostly remembered for Heron's formula, a way to calculate the area of a triangle using only the lengths of its sides.
Hero published a well-recognized description of a steam-powered device called an aeolipile, also known as "Hero's engine". Among his most famous inventions was a windwheel and a pantograph. Some of his ideas were derived from the works of Ctesibius.
