Continuing the series of 'greatest contributions to the world', it would be har to miss China. Interestingly, many things that appear to be part of Japanese culture are in fact Chinese (fireworks, wood block printing, kanji, Confucianism, rice paper, rice cultivation, noodles, etc.).

Note that I did not include the compass in the list, as it is mostly a myth that the Chinese invented (there is no tangible evidence that they were the first).