title: Is there a overall explanation about definitional scoping in Rebol and Red
body: <p>From the <a href="http://www.rebol.com/docs/core23/rebolcore-9.html#section-9" rel="noreferrer">REBOL/Core Users Guide</a>, and <a href="http://static.red-lang.org/Recode2013-Red.pdf" rel="noreferrer">What is Red</a>, I have learned that both Rebol and Red use <strong>definitional scoping</strong>.</p>
  
  <p>From the guide, I know it is a form of <strong>static scoping</strong>, "the scope of a variable is determined when its context is defined", and is also called <a href="http://www.rebol.com/r3/notes/errors.html" rel="noreferrer"><strong>runtime lexical scoping</strong></a>, and is <a href="https://www.mail-archive.com/list@rebol.com/msg08421.html" rel="noreferrer">a dynamic form of static scoping that depends on context 
  definitions</a>.</p>
  
  <p>I know in com-sci, there are two forms of scoping: lexical scoping (static scoping) and dynamic scoping. This <em>definitional scoping</em> confused me.</p>
  
  <p>So what is definitional scoping? </p>