div, table, tr, td 숨기기/보이기

<!-- 위치가 당겨짐 -->
document.all.id_name.style.display = "block";  
document.all.id_name.style.display = "none";


<!-- 위치가 안 당겨짐 -->
document.all.id_name.style.visibility = "visible";
document.all.id_name.style.visibility = "hidden";