$(function() {
  function setExplanation(text) {
    $("#nav span").html(text).show();
  }
  
  function clearExplanation() {
    $("#nav span").html(" ").hide();
  }
  
  $("#info-link").hover(function() {
    setExplanation("About Us >>");
  }, function() {
    clearExplanation();
  });
  
  $("#blog-link").hover(function() {
    setExplanation("LightRail Blog >>");
  }, function() {
    clearExplanation();
  });
  
  $("#products-link").hover(function() {
    setExplanation("Products and Services  >>");
  }, function() {
    clearExplanation();
  });
  
  $("#mail-link").hover(function() {
    setExplanation("Contact LightRail  >>");
  }, function() {
    clearExplanation();
  });
});