var expDays = 120;
var exp = new Date(); 
exp.setTime(exp.getTime() + (expDays*24*60*60*1000));
<!-------------------------------------------
function getCookieVal (offset) {  
var endstr = document.cookie.indexOf (";", offset);  
if (endstr == -1)    
endstr = document.cookie.length;  
return unescape(document.cookie.substring(offset, endstr));
}
<!--------------------------------------------
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 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 DeleteCookie (name) {  
var exp = new Date();  
exp.setTime (exp.getTime() - 1);  
var cval = GetCookie (name);  
document.cookie = name + "=" + cval + "; expires=" + exp.toGMTString();
}
<!----LEZEN--//-->


function getname()
{

var naam = GetCookie('Nama');
if (naam == null) {naam = '';}

return naam;
}

function getaantal()
{

var get = GetCookie('Aantal');
if (get == null) {get = '';}

return get;
}
<!------SCRIJVEN--//-->
function setname(xxx)
{

SetCookie ('Nama', xxx, exp);

}


function setaantal(nr)
{

SetCookie ('Aantal', nr, exp);
}
<!-----------NIET COOKIES--//-->
function zetnaam()
{
var grh=document.form1.nm.value;
if (document.form1.nm.value==''){alert('please enter your name');}
else {setname(grh);setaantal('1');history.go(0);}



}

function add()
{
var nmbr=getaantal();
if (nmbr==''){}
else {
	nnnn=parseInt(nmbr)+1;
	setaantal(parseInt(nnnn));
     }
}



function welkom()
{
var wie=getname();
var nmbr=getaantal();
if (wie=='')
	{
	document.write('Welcome at the Anchor Point site.<br>You are visitor number <img src="http://s11.sitemeter.com/meter.asp?site=s11anchorpoint"><br>');
        document.write('Please enter your name in the textfield below so we can adress you by name.</font><br>');
    	document.write('<form name="form1" method="post" action=""><input type="text" name="nm"><input type="button" value="go" name="Button" onClick="zetnaam()"></form>');
	}
else
	{
	
	
	document.write('Welcome back at the Anchor Point site, '+wie+'. <br>');
	document.write('You are visitor number <img src="http://s11.sitemeter.com/meter.asp?site=s11anchorpoint"><br><br>');
	}
}