What is a whitelist?
Whitelist helps you sort good addresses from the ones you do not like. It contains all the addresses that you have approved and therefore prevents the use of potentially dangerous web pages.
The whitelist can be used to restrict access to your pages. It contains only specific IP addresses, from which your agents, admins, and owners can log in.
Another use of Whitelist is in keeping track of profitable placements. When you come across a site that is suitable for your business, you simply add it to Whitelist to remember it.