This textbook covers neuroscience from cellular and molecular mechanisms to behavior and cognitive processing. We also address  evolution of the nervous system, computational neuroscience, the history of neuroscience as a discipline and neurophilosophy – to name but a few. The book provides the newest state-of-the-art knowledge about neuroscience from across the animal kingdom, with particular emphasis on model species commonly used in neuroscience labs across the world: mouse, zebra fish, fruit fly, honeybee, and nematode worm. We aim at university students of neuroscience, psychology, biological sciences, and medical sciences, but also computer scientists, philosophers, or anybody interested in understanding how brains work.