function getBrowserType()
{
  var agent = navigator.userAgent.toLowerCase();

  if(agent.indexOf('firefox') != -1){
    return "ff";
  }
  else if(agent.indexOf('opera') != -1){
    return "op";
  }
  else if(agent.indexOf('chrome') != -1){
    return "ch";
  }
  else if(agent.indexOf('safari') != -1){
    return "sa";
  }
  else if(agent.indexOf('msie') != -1){
    return "ie";
  }
  else{
    return "un";
  }
}