Unknown

Unknown or The Unknown may refer to:

Mathematics

Film

Music

Other uses

Dream

Dreams are successions of images, ideas, emotions, and sensations that occur usually involuntarily in the mind during certain stages of sleep. The content and purpose of dreams are not definitively understood, though they have been a topic of scientific speculation, as well as a subject of philosophical and religious interest, throughout recorded history. The scientific study of dreams is called oneirology.

Dreams mainly occur in the rapid-eye movement (REM) stage of sleep—when brain activity is high and resembles that of being awake. REM sleep is revealed by continuous movements of the eyes during sleep. At times, dreams may occur during other stages of sleep. However, these dreams tend to be much less vivid or memorable.

The length of a dream can vary; they may last for a few seconds, or approximately 20–30 minutes. People are more likely to remember the dream if they are awakened during the REM phase. The average person has three to five dreams per night, and some may have up to seven; however, most dreams are immediately or quickly forgotten. Dreams tend to last longer as the night progresses. During a full eight-hour night sleep, most dreams occur in the typical two hours of REM.

Fact

A fact is something that has really occurred or is actually the case. The usual test for a statement of fact is verifiability—that is, whether it can be demonstrated to correspond to experience. Standard reference works are often used to check facts. Scientific facts are verified by repeatable careful observation or measurement (by experiments or other means).

Etymology and usage

The word fact derives from the Latin factum, and was first used in English with the same meaning: a thing done or performed, a meaning now obsolete. The common usage of "something that has really occurred or is the case" dates from the middle of the sixteenth century.

Fact is sometimes used synonymously with truth, as distinct from opinions, falsehoods, or matters of taste. This use is found in such phrases as, "It is a fact that the cup is blue" or "Matter of fact", and "... not history, nor fact, but imagination." Filmmaker Werner Herzog distinguishes clearly between the two, claiming that "Fact creates norms, and truth illumination."

Sweet Dreams

Sweet Dreams may refer to:

Music

Albums

Songs