function setCookie (name, value, expires) {
        if (!expires) expires = new Date();
	document.cookie = name + "=" + escape (value) + 
	"; expires=" + expires.toGMTString() ;
}

==================

function delCookie (name) {
	var expireNow = new Date();
	document.cookie = name + "=" +
	"; expires="+ expireNow.toGMTString();
}

===================
//comments in the following function refer to the line immediately above the comment
function getCookie (name) {
	var dcookie = document.cookie; 	
//puts the cookie into a string called dcookie
	var cname = name + "=";		
// sets cname to the name of the cookie followed by an =
	var clen = dcookie.length;		
// sets clen = the length of the cookie
	var cbegin = 0;	
        while (cbegin < clen) {			
// as long as there's still somewhere to look in the cookie
        var vbegin = cbegin + cname.length;	
// vbegin is the place where the value should begin
                if (dcookie.substring(cbegin, vbegin) == cname) {   
// this looks for the name of the cookie within the string between positions cbegin and vbegin
                var vend = dcookie.indexOf (";", vbegin);	
// sets the end of the value at the location of the first semi-colon following vbegin
                        if (vend == -1) vend = clen;		
// if this was the last cookie the semi-colon would be missing so use the end of the cookie instead
                return unescape(dcookie.substring(vbegin, vend));	
// this sends the value back and simultaneously exits from the function
                }
// end of the if statement
        cbegin = dcookie.indexOf(" ", cbegin) + 1;
//moves cbegin up to the position following the next blank space to continue looking
                if (cbegin == 0) break;
// if  no spaces were found then exit the while loop
        }
return null;
// return nothing since the cookie wasn't found.
//NOTE: if it had been found the return 11 lines up would have  sent the value back when the function was exited
}