I was not aware that there are "approximately 300 ccTLDs" and I was also not aware that "tk (Tokelau)" was a country domain. I had an impression that dot tk was a freenom domain that does not require money to register and use. I even did not know a place called Tokelau existed. I just googled and found that it is a country in the pacific ocean.ccTLD (Country Code Top-level Domain) is a two-letter domain extension used primarily to identify an association of some kind to a specific country or territory. There are approximately 300 ccTLDs, with over 150 million domains registered using one of them.
The five most popular ccTLDs are .cn (China), .tk (Tokelau), .de (Germany), .uk (United Kingdom), and .tw (Taiwan).