Update

randomness.md

@@ -2,7 +2,7 @@
 
 *Not to be [confused](often_confused.md) with [pseudorandomess](pseudorandomness.md).*
 
-Randomness means unpredictability, lack of patterns, and/or events without (apparent) cause. Random events can only be predicted imperfectly using [probability](probability.md) because there is something present that's subject to chance, something we don't know; events may be random to us either because they are inherently random (i.e. they really have no cause, pattern etc.) or because we just lack knowledge, understanding or practical ability (e.g. enough computational power) to perfectly predict the events. Randomness is one of the most basic, yet also one of the most difficult (and fascinating) concepts to understand about our [Universe](universe.md) -- it's a phenomenon of uttermost practical importance, we encounter it every second of our daily lives, but it's also of no lesser interest to [science](science.md), philosophy, [art](art.md) and [religion](religion.md). Whole libraries could be filled just with [books](books.md) about this subject, here we will be able to only scratch the surface by taking a high altitude overview of randomness, mostly as related to [programming](programming.md) and [math](math.md). Randomness (and pseudorandomness) is one of the things that **can bring a lot of [fun](fun.md) into [programming](programming.md)** -- it's quite simple but very entertaining to create generators of various random things such as [music](music.md), novels (see e.g. [nanogenmo](nanogenmo.md)), pictures, randomly behaving bots and so on.
+Randomness means unpredictability, lack of patterns, and/or events without (apparent) cause. Random events can only be predicted imperfectly using [probability](probability.md) because there is something present that's subject to chance, something we don't know; events may be random to us either because they are inherently random (i.e. they really have no cause, pattern etc.) or because we just lack knowledge, understanding or practical ability (e.g. enough computational power) to perfectly predict the events. Randomness is one of the most basic, yet also one of the most difficult (and fascinating) concepts to understand about our [Universe](universe.md) -- it's a phenomenon of uttermost practical importance, we encounter it every second of our daily lives, but it's also of no lesser interest to [science](science.md), philosophy, [art](art.md) and [religion](religion.md). Whole libraries could be filled just with [books](books.md) about this subject, here we will be able to only scratch the surface by taking a high altitude overview of randomness, mostly as related to [programming](programming.md) and [math](math.md). Randomness (and pseudorandomness) is one of the things that **can bring a lot of [fun](fun.md) into [programming](programming.md)** -- it's quite simple but very entertaining to create generators of various random things such as [music](music.md), novels (see e.g. [nanogenmo](nanogenmo.md)), pictures, randomly behaving bots and so on. Among the most commonly used sources of "true randomness" are dice throws, coin flips, cosmic background radiation noise, Brownian motion, measurements of [quantum](quantum.md) properties such as radioactive decay etc.
 
 As with similarly wide spanning terms, the word *randomness* and *random* may be defined in different ways and change meaning slightly depending on context, for example sometimes we have to distinguish between "true" randomness, such as that we encounter in [quantum mechanics](quantum.md) or that present in nondeterministic mathematical models, and [pseudorandomness](pseudorandomness.md) (what as a programmer you'll be probably dealing with), i.e. imitating this true randomness with [deterministic](determinism.md) ("non-randomly behaving") systems, e.g. sequences of numbers that are difficult to [compress](compression.md). Other times we call random anything at all that just deviates from usual order, as in "someone started randomly spamming me in chat". Sometimes there are slight nuances in the meaning, for example by the word "random" we can mean "generated by a randomly behaving process", but also for example "data having statistical properties the same as if they were generated by a random process". Sometimes the distinctions don't matter too much, sometimes they do. Let's briefly review a few terms related to this topic: