function toggle_visibility(id) {
       var e = document.getElementById(id);
       if(e.style.display == 'block')
          e.style.display = 'none';
       else
          e.style.display = 'block';
    }

    function displayAnnouncements(thisTab) {
       var e = document.getElementById('homeTab1');
       e.style.backgroundPosition='0px 0px';
       var e = document.getElementById('homeTab2');
       e.style.backgroundPosition='bottom left';
       var e = document.getElementById('homeTab3');
       e.style.backgroundPosition='bottom left';
       var e = document.getElementById('announcementList');
       var e = document.getElementById('announcementList');
       e.style.display = 'block';
       var e = document.getElementById('majorEventList');
       e.style.display = 'none';
       var e = document.getElementById('programList');
       e.style.display = 'none';
    }

    function displayMajorEvents(thisTab) {
       var e = document.getElementById('homeTab1');
       e.style.backgroundPosition='bottom left';
       var e = document.getElementById('homeTab2');
       e.style.backgroundPosition='0 0';
       var e = document.getElementById('homeTab3');
       e.style.backgroundPosition='bottom left';
       thisTab.style.background='url(../pics/homeTabBackground.gif) 0px 0px no-repeat';
       var e = document.getElementById('announcementList');
       e.style.display = 'none';
       var e = document.getElementById('majorEventList');
       e.style.display = 'block';
       var e = document.getElementById('programList');
       e.style.display = 'none';
    }

    function displayPrograms(thisTab) {
       var e = document.getElementById('homeTab1');
       e.style.backgroundPosition='bottom left';
       var e = document.getElementById('homeTab2');
       e.style.backgroundPosition='bottom left';
       var e = document.getElementById('homeTab3');
       e.style.backgroundPosition='0 0';
       thisTab.style.background='url(../pics/homeTabBackground.gif) 0px 0px no-repeat';
       var e = document.getElementById('announcementList');
       e.style.display = 'none';
       var e = document.getElementById('majorEventList');
       e.style.display = 'none';
       var e = document.getElementById('programList');
       e.style.display = 'block';
    }