Delta waves are a type of brainwave that occur during deep sleep and are characterized by their slow frequency, typically ranging from 0.5 to 4 Hz. These waves are essential for restorative sleep, helping the body and mind recover and rejuvenate. Delta waves are most prominent in the NREM sleep stages, particularly during stage 3 sleep, which is crucial for physical healing and growth. In addition to their role in sleep, delta waves are also associated with deep meditation and relaxation. They can indicate a state of unconsciousness or deep tranquility, allowing for profound mental and emotional healing. Understanding delta waves can help in exploring the benefits of sleep hygiene and meditation practices.