Discovery of the Cell

In 1665 the English scientist Robert Hooke examined a thin slice of cork under a microscope of his own design and observed a honeycomb like structure of small compartments, which he named cells after the Latin word for a small room, describing the empty spaces left behind in the once living plant tissue. His observation, published in his book Micrographia, gave biology its basic unit of structure long before anyone understood what a cell actually did, and it laid the groundwork for the cell theory that Matthias Schleiden and Theodor Schwann would formulate for plants and animals nearly two centuries later.