JS: Check if date is less than 1 hour ago?

Question

Is there a way to check if a date is less than 1 hour ago?

Something like this:

Answer 1

//for adding hours to a date
Date.prototype.addHours= function(hrs){
    this.setHours(this.getHours()+hrs);
    return this;
}

Call function like this:

//test alert(new Date().addHours(4));