The document discusses several common sleep disorders: insomnia, sleep apnea, narcolepsy, and hypersomnia. Insomnia is difficulty falling or staying asleep and can be caused by stress, drugs, or changes in sleep schedule. Sleep apnea involves stopping breathing periodically during sleep and is linked to obesity. Narcolepsy involves sudden sleep attacks during wakefulness. Hypersomnia causes excessive daytime drowsiness or longer than average nighttime sleep. Treatments range from lifestyle changes, drugs, surgery, or devices depending on the specific disorder.