What are "Ambient Typings" in the Typescript Typings tool? : <p>I hear the term "ambient" used to describe type definitions downloaded with the <a href="https://github.com/typings/typings">typings</a> tool. What does that mean, though?</p>

<p>I can't seem to find a straightforward definition of it or the <code>--ambient</code> flag.</p>
