This document provides information about Dr. Mohammed Hussein, a psychiatrist in Egypt. It discusses his qualifications and role as technical manager and editor of the website "tabibnafsany.com". The document then provides summaries of sleep architecture and cycles, common sleep disorders, and healthy sleep hygiene practices. It notes that sleep varies between individuals based on factors like age, gender, environment and health conditions. Non-rapid eye movement sleep and rapid eye movement sleep are summarized. Common causes of poor sleep and their treatment are also outlined.