Is it safe to compare JavaScript's getTime() across different systems?
<p><a href="https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Date/getTime">JavaScript's getTime()</a> returns "the number of milliseconds since 1 January 1970 00:00:00 UTC".</p>

<p>Can I rely on this being similar across different machines? I don't need it to be accurate to the millisecond, just to a few seconds.</p>

<p>Or do I need to use an external time service API, <a href="http://stackoverflow.com/questions/489581/getting-the-current-gmt-world-time">as in this question</a>?</p>

<p>Where does JavaScript get the current time from - is it dependent on the machine's clock?</p>
