Topics: sleep disorders, Measuring sleep, Stages of Sleep, sleep cycle, NON-REM SLEEP, Sleep hypnogram, Idealized normal hypnogram, ICSD-3, DSM 5, Sleep-wake disorders, dyssomnias, Intrinsic sleep disorders, Extrinsic sleep disorders, Circadian Rhythm Sleep Disorders, parasomnias, Arousal Disorders, nightmares, sleep paralysis, Insomnia, Psychophysiologic insomnia, Sleep-Related Movement Disorders, Restless leg syndrome, periodic limb movement of sleep, Sleep diary, Actigraphy, Polysomnography, Hypersomnia, Kleine-Levin Syndrome, Recurrent Hypersomnia, Sleep hygiene, hypnotic drugs