Here's a breakdown:

* Robert Hooke was an English scientist, architect, and polymath.

* He used a primitive microscope to examine a thin slice of cork.

* He observed small, box-like compartments that he called "cells" because they reminded him of the cells of a monastery.

This discovery was a significant step forward in our understanding of living organisms. It laid the foundation for the cell theory, which states that all living things are made up of cells, and that cells are the basic unit of life.