title: Is the difference between two UNIX TIMESTAMPs in two machines different?
body: <p>I have a script that subtracts a unix timestamp from the timestamp representing the current time in javascript:</p>
  
  <pre><code>  var d1=new Date(1385890985000);//UNIX TIMESTAMP IN MILLISECONDS 
    var d2=new Date();
  
    var t1=d1.getTime();
    var t2=d2.getTime();
  
        if(t2-t1&lt;60*60*1000)//1 hour
        {        
          alert(Math.floor((t2-t1)/60000)+" minute ago");                 
        } 
        else if(t2-t1&lt;24*60*60*1000)//24 hours
        {        
          alert(Math.floor((t2-t1)/3600000)+" hour ago");                
        }
  </code></pre>
  
  <p>The script is fine in showing the difference of time in minutes or hours,such as 10 minutes ago or 7 hours ago etc.I have tested it in local timezone or with any other timezone and found it ok! But today in my college lab when I tried it in some of the machines it was again just fine with a disappointment in two machines with different timezones that show the difference differently: one shows 6 hours ago and the other shows 6 minutes ago although it shouldn't be so. Because UNIX timestamp is nothing but the numbers of seconds elapsed from the epoch year 1970 January 1. What is the wrong here? Any suggestions,tips or words of lesson is appreciated! All machines are lenovo desktop with Windows XP installed.</p>