title: What is the meaning of "POSIX"?
body: <p>What is POSIX? I have read the <a href="http://en.wikipedia.org/wiki/POSIX" rel="noreferrer">Wikipedia article</a> and I read it every time I encounter the term. The fact is that I never really understood what it is.</p>
  
  <p>Can anyone please explain it to me by explaining "the need for POSIX" too?</p>