Sleeping well is important for our organism, it is as essential as eating and breathing. Even if you don't believe it while we sleep, our body is still active, as it boosts defenses, regulates growth, body weight and also helps the brain to learn.
During the night we go from 4 to 5 sleep cycles that last about 90 minutes, first we enter into a light sleep, which gradually becomes deeper, it is at that stage in which the brain is activated and performs the necessary biological activities.
Dreams last from 3 to 4 minutes and if you remember one, it is because you dreamed it just before the alarm clock rang, that's why it seemed that the dream lasted all night.
(Source)[https://www.verywellmind.com/facts-about-dreams-2795938 ]
