Dreams occur during the REM phase of sleep, which is generalized and common to all human beings. Hence everybody's sleep has this dream state or REM sleep state. In case your sleep is interrupted in the REM phase, you have a clearer memory and imagery of the dream. Sleep requirement differs in different people. Short sleepers require fewer than 6 hours of sleep each night whereas long sleepers are those who sleep more than 9 hours each night in order to function adequately.
Short sleepers are generally efficient, ambitious, socially adept and content.
Long sleepers tend to be mildly depressed, anxious and socially withdrawn. Increased sleep occurs with physical work, exercise, illness, pregnancy, general mental stress and increased mental activity. Don't deprive yourself of sleep. Sleep is crucial for normal thermoregulation and energy conservation. It is the restoration, allowing your body and mind to recuperate and achieve the right homeostatic balance.