jQuery stick to the top of the page header

Sticky Header

$(function() {

         var schtickm = $("header"), pos = schtickm.offset();

         $(window).scroll(function() { 

                  if($(this).scrollTop() > (pos.top + 10) &&
                  schtickm.css('position') == 'static') { schtickm.addClass('fixed'); } 
             
                  else if($(this).scrollTop() <= pos.top &&
                  schtickm.hasClass('fixed')){ schtickm.removeClass('fixed'); }
         })
});

This assumes the css of the header has a position rule of static.

.fixed{
position: fixed;
top:0;
bottom:0;
}