The neurobiology of sleep delves into the intricate mechanisms governing the fundamental biological process of sleep. Sleep regulation involves a complex interplay of neuronal circuits, neurotransmitters, and various brain regions. Key players like the brainstem, hypothalamus, and thalamus orchestrate the initiation and regulation of sleep cycles. The sleep-wake cycle hinges on the interaction between the sleep-promoting system, including the ventrolateral preoptic nucleus (VLPO) in the hypothalamus, and the wake-promoting system, which involves brainstem and hypothalamic histaminergic neurons. Neurotransmitters such as serotonin, dopamine, norepinephrine, and acetylcholine modulate these systems, influencing sleep stages and transitions. Serotonin and norepinephrine help maintain wakefulness, whereas gamma-aminobutyric acid (GABA) and adenosine promote sleep. Sleep comprises distinct stages characterized by specific brain wave patterns and physiological changes, encompassing non-rapid eye movement (NREM) and rapid eye movement (REM) sleep. Understanding the neurobiology of sleep is crucial for unraveling sleep-related disorders and developing targeted interventions to improve sleep quality and overall health. Researchers continue to explore the intricate mechanisms underlying sleep regulation to pave the way for more effective therapeutic strategies.