What is a cell?
A cell is the basic unit of life in any organism. They are also the building blocks of life. One of the first people to observe cells was Robert Hook. But without microscopes, Hook couldn't have made history. Microscopes made it possible for people to learn about cells. In fact in 1663, Hook observed a thin slice of a cork with a compound microscope he had built himself. About the time that Hook made his discovery, Anton van Leeuwenhoek also began to observe tiny objects.
