Cookies refresh depending on their time settings. Some cookies like the login cookie of WebmasterWorld reside on your computer for years and even survive when your browser is closed or the computer is restarted. Others have a lifetime just as long as the browser session is open.

As far as I have seen in my testing, cookies without a lifetime setting and which would therefore be killed once the browser is closed survive a page refresh. But cookies which have a short lifetime setting are refreshed if the page refresh takes place after the lifetime of the cookie has passed.

Mostly correct, cookies without a valid expiration date/time (called session cookies) die when the browser is closed. But cookies with a valid expiration date/time (called persistent cookies) *may or may not* be refreshed, depending on the mechanism setting the cookie (server side programming or Javascript, examples.)

For example, a (poorly designed?) login scheme may set a cookie with a valid expiration date/time when you first log in, and never reset after that point. So let's say it's one hour in the future. As you navigate around the site, an hour later *poof* you have to log in again because the cookie expires.

Another (better designed?) login scheme would keep extending the hour out by resetting that cookie each time you navigate to another page - or refresh the page. So in this case, the answer would be yes, refreshing the page would "refresh" the cookie. It depends on how the site is coded.