The discovery and understanding of cells is a fundamental part of the history of biology and microscopy. Here is a timeline of key events and discoveries in the field of cell biology:

1. 1665 – Robert Hooke: The English scientist Robert Hooke is often credited with the first description of cells. He used a primitive microscope to examine a thin slice of cork and observed small, box-like structures, which he called “cells” (from the Latin word “cella,” meaning small room).
2. 1673 – Anton van Leeuwenhoek: The Dutch scientist Anton van Leeuwenhoek was one of the first to build high-quality microscopes. He observed single-celled microorganisms, which he called “animalcules,” in various biological samples, including pond water and dental plaque.
3. 1838 – Matthias Schleiden: The German botanist Matthias Schleiden proposed the idea that all plant tissues are composed of cells. This marked the beginning of the cell theory.
4. 1839 – Theodor Schwann: The German biologist Theodor Schwann, working independently from Schleiden, extended the cell theory to include animals. He proposed that all animals are made up of cells.
5. 1855 – Rudolf Virchow: The German physician and pathologist Rudolf Virchow contributed to the cell theory by stating that all cells arise from pre-existing cells. His famous maxim, “Omnis cellula e cellula” (Every cell originates from another cell), laid the foundation for the concept of cell division and the continuity of life.