What is significant about Zheng He’s fleet of ships?

They were enormous (over 400 feet long and 7+ masts) , he had an armada of over 300 with a crew of over 27,000. It is noted that Zheng He wasn't an explorer but a mariner whose journeys were trade missions. ... Zheng He and his patron the Yongle Emperor died.

its many islands, high mountains, and remote peninsulas isolated population centers.

most people now work in jobs where they do one  kind  of work; they are carpenters, bankers, cooks, mechanics, and so forth. likewise, most  businesses produce  only certainkinds  of  goods  or  services, such as cars, tacos, or gardening  services. this feature of  production  is known as specialization.