Как работать с куками. cookies.

var expDays = 1;

function GetCookie (name) {   
var arg = name + "=";   
var alen = arg.length;   
var clen = document.cookie.length;   
var i = 0;   
while (i < clen) {   
var j = i + alen;   
if (document.cookie.substring(i, j) == arg)   
return getCookieVal (j);   
i = document.cookie.indexOf(" ", i) + 1;   
if (i == 0) break;   
}   
return null;
}
function SetCookie (name, value) {   
var argv = SetCookie.arguments;   
var argc = SetCookie.arguments.length;   
var expires = (argc > 2) ? argv[2] : null;   
var path = (argc > 3) ? argv[3] : null;   
var domain = (argc > 4) ? argv[4] : null;   
var secure = (argc > 5) ? argv[5] : false;   
document.cookie = name + "=" + escape (value) +   
((expires == null) ? "" : ("; expires=" + expires.toGMTString())) +   
((path == null) ? "" : ("; path=" + path)) +   
((domain == null) ? "" : ("; domain=" + domain)) +   
((secure == true) ? "; secure" : "");
}
function DeleteCookie (name) {   
var exp = new Date();   
exp.setTime (exp.getTime() - 1);   
var cval = GetCookie (name);   
document.cookie = name + "=" + cval + "; expires=" + exp.toGMTString();
}
var exp = new Date();   
exp.setTime(exp.getTime() + (expDays*24*60*60*1000));
function amt(){
var kulda = GetCookie('kulda')
if(kulda == null) {
SetCookie('kulda','1')
return 1
}
else {
var newkulda = parseInt(kulda) + 1;
DeleteCookie('kulda')
SetCookie('kulda',newkulda,exp)
return kulda
}
}
function getCookieVal(offset) {
var endstr = document.cookie.indexOf (";", offset);
if (endstr == -1)
endstr = document.cookie.length;
return unescape(document.cookie.substring(offset, endstr));
}

function checkkulda() {
var kulda = GetCookie('kulda');
if (kulda == null) {
kulda=1;
SetCookie('kulda', kulda, exp);

document.getElementById('magicnew').style.display = 'block';
document.getElementById('magicwas').style.display = 'none';
}
else {
kulda++;
SetCookie('kulda', kulda, exp);
}
}

<a href="javascript://" onclick="checkkulda();">тык</a>
<div id="magicwas">111111</div>
<div id="magicnew" style="display:none;">22222</div>