The cell is the basic structural, functional, and biological unit of all known living organisms. A cell is the smallest unit of life that can replicate independently, and cells are often called the “building blocks of life”. The study of cells is called cell biology. Cell biology is a branch of biology that studies the different structures and functions of the cell and focuses mainly on the idea of the cell as the basic unit of life. Cell biology explains the structure, organization of the organelles they contain, their physiological properties, metabolic processes, Signaling pathways, life cycle, and interactions with their environment. This is done both on a microscopic and molecular level as it encompasses prokaryotic cells and eukaryotic cells. Knowing the components of cells and how cells work is fundamental to all biological sciences; it is also essential for research in bio-medical fields such as cancer, and other diseases. Research in cell biology is closely related to genetics, biochemistry, molecular biology, immunology, and developmental biology. By delving into various aspects of cell biology, this book aims to foster a comprehensive understanding among its readers. The discussions within the book cover a wide range of topics, enabling readers to gain insights into the diverse facets of cell biology. The content is designed to facilitate understanding and learning, providing readers with a solid foundation in cell biology. The book incorporates current research and discoveries, offering readers an up-to-date perspective on the field.