What is "Refresh" on main page and game pages?

The "Refresh" value means the automatic refresh period of all related pages (i.e. main page and game pages waiting for the opponent's turn). This feature was requested by several users who wanted to be still informed about the status of their started games without manual clicking on "Main page" link.
If you set Refresh to some non-zero value and nothing happens after the selected time period, your browser probably does not support automatic page refresh.