While he wasn't the first to *see* cells, he was the first to name them and describe their structure. In 1665, using an early compound microscope, Hooke observed thin slices of cork and noticed small, box-like compartments that reminded him of the cells of a monastery. He called these compartments "cells."

However, it's important to note that Hooke was looking at the empty cell walls of dead plant cells. It wasn't until later that other scientists, like Antonie van Leeuwenhoek, observed living cells.