In 1665, Hooke used a primitive microscope to examine a thin slice of cork. He observed small, box-like compartments that reminded him of the cells in a monastery. He called these compartments "cells" because they resembled the small rooms where monks lived.
While Hooke didn't see the living cells, he did identify these structures as fundamental building blocks of the cork tissue. His discovery was a significant contribution to our understanding of living organisms and paved the way for later scientists to delve deeper into the world of cells.