Passwords often seem to be not crackable, but watch this video and you will change your Password habit.
Randomness is the lack of pattern or predictability in events. A random sequence of events, symbols or steps has no order and does
not follow an intelligible pattern or combination. Individual random events are by definition unpredictable, but in many cases the frequency of
different outcomes over a large number of events (or "trials") is predictable. For example, when throwing two dice, the outcome of any particular
roll is unpredictable, but a sum of 7 will occur twice as often as 4. In this view, randomness is a measure of uncertainty of an outcome, rather
than haphazardness, and applies to concepts of chance, probability, and information entropy.
(by Wikipedia,
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Veritasium has made a great Video about randomness. He discusses randomness, entropy and the vision by Laplace, who discussed,
that everything about the future could be known if we knew the position and speed by any particle in the universe.
Here is the Video: