The 245 ccTLDs, all two-digit codes, cover all UN-recognised countries, plus several non-sovereign islands and territories. This map, designed by John Yunker (website here), presents those codes in a size relative to the population of each country or territory – except China and India, which were restrained by 30% to fit the layout. The smallest type size reflects all countries with 10 million inhabitants or less.
And here is a funny explanation, by comparison with the www, of what a library is.
(Thanks to Alex Nadaban for this.)