Mammalian cells are the basic building blocks of mammals, including humans. They are eukaryotic cells, meaning they have a defined nucleus and organelles that perform specific functions. These cells can be found in various tissues and organs, playing crucial roles in processes like growth, metabolism, and immune response. Mammalian cells can be classified into different types, such as muscle cells, nerve cells, and blood cells, each specialized for particular functions. They reproduce through a process called mitosis, allowing for growth and repair. Understanding mammalian cells is essential for fields like medicine and biotechnology.