Why there is an existing default cookie name in Cookie in GWT?

Why there is an existing default cookie name in Cookie in GWT?

I just found out that there is an existing default cookie name in Cookie
before i actually adds my cookie name into it.
Collection<String> cookies = Cookies.getCookieNames();
for (String cookie : cookies) {
String cookieValue = Cookies.getCookie(cookie);
String[] itemMeaningIDcompanyMeaningID=cookie.split("_");
}
If i live the default cookie there, then i have a problem cos I need to
convert cookie name into array so i may split the default cookie & that
could cause runtime error.
i suspect that the default cookie is used for something else in GWT, so if
i remove it then the system may not run properly.
So my question is, should i remove that default cookie or i just leave it
there?