Galileo Galilei (1564–1642) was an Italian physicist, astronomer, and mathematician. He is widely considered one of the founders of modern science because he helped develop a new way of studying nature using observation, experiments, and mathematics.

Galileo was born in Pisa, Italy, and was the oldest of six children. His father, Vincenzo Galilei, was a musician and scholar who encouraged questioning traditional ideas and testing them through experiments. This way of thinking strongly influenced Galileo.

As a young boy, Galileo studied at a monastery school in Vallombrosa and briefly considered becoming a monk. At age 16, he enrolled at the University of Pisa to study medicine, hoping to become a doctor. However, he soon became fascinated with mathematics after attending a lecture on geometry.

Eventually, Galileo decided to stop studying medicine. He left the university in 1585 without a degree and began supporting himself by teaching mathematics. Later, he became a professor and continued studying physics and astronomy.