title: Why nomalise a float &... why is alpha a 0 to 1 float point number in CSS rgba()
body: <p>to-the-point question here. sorry.</p>
  
  <p>I am trying to understand *normalization** in terms of mathematics. </p>
  
  <p>In the <a href="http://toxiclibs.org/" rel="nofollow noreferrer">toxiclibs</a> library one can normalise a float. Why one would want to normalize a float... In 3D I get that a normal of 3 dimentional plane can give the <em>up</em>. First thought: it is to do with preformance. But then I found this <a href="https://stackoverflow.com/questions/3081536/when-to-normalize-a-vector">SO question</a> explaining how a game UI may use it. This... I kind of get. </p>
  
  <p>Would it be fair to say one would normalised a float where there is a max and minimum? Two scenarios I can think of:</p>
  
  <ol>
  <li><p>CSS Color RGBA: RGB is from 0 to 255 but could, theoretically, go higher. Whereas A is from 0.0 to 1.0. Is this normalized as it can be completely transparent or opaque, therefore it is a normal because there is a definative 0 or 1?</p></li>
  <li><p>When recording music (or looking at a wave form), it can be clipped. Is this because there is a max and a min, so a normalized value above 1 would be clipped? I guess, in this case, normalise would be for convenience.</p></li>
  </ol>
  
  <p>So, why normalize a float? Is it performance? Readabilty? Something else (visual reference == Kudos)? Does a Spinal Tap Amp going all the way up to 11 have anything to do with this?</p>