Javascript snippet for plain english relative time (e.g. "X seconds ago")

timeago.js

function time_ago(time) {
    periods = new Array("second", "minute", "hour", "day", "week", "month", "year", "decade");
    lengths = new Array("60","60","24","7","4.35","12","10");
    
    nowdate = new Date();
    now = (nowdate.getTime() / 1000);
    
    difference = now - time;
    tense = "ago";
    
    for(j = 0; difference >= lengths[j] && j < lengths.length-1; j++) {
        difference /= lengths[j];
    }
    
    difference = Math.round(difference);
    
    if(difference != 1) {
        periods[j] += "s";
    }
    
    return difference + ' ' + periods[j] + ' ago';
}