In computing, a blacklist is a basic access control mechanism that allows everyone access, except for the members of the black list (i.e. list of denied accesses). The opposite is a whitelist, which means allow nobody, except members of the white list.
Do you want to block unwanted vsitors from certain countries?
Try IP Blocker Firewall to block country IP addresses.
Please find up-to-date country IP address lists from I-Blocklist.