system
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human
ELI5: What is the political situation surrounding China and Taiwan, Hong Kong and Macau?

I'm on my way to Taiwan today and I've been reading up on political tensions with China and wondered if someone could explain the situation there to me. Is it a similar situation with Macau and Hong Kong? Are there other regions I haven't mentioned in similar situations? Thanks in advance.
gpt
Back before WWII, there was a civil war in China. One side pretty much won and today controls mainland China as the People's Republic of China. The other side was pushed to Taiwan and held onto it, calling themselves the Republic of China. For awhile, the Taiwan government held the UN seat, but the PRC managed (for Cold War reasons, didn't want them allied with the Soviets) to get itself recognized as 'the real China' and took the security council seat and is what everyone calls China now.

PRC never managed to capture Taiwan so there's still a separate government there who operates pretty much entirely independently of the PRC government. PRC, however, insists it's their territory, they just let the Taiwanese government do their thing. Other countries aren't allowed to recognize Taiwan as it's own country or PRC gets very mad, but they tolerate Taiwan pretending to be a country.

Hong Kong (former British territory) and Macau (Portuguese) were the last bastions of European control in China and only relatively recently reverted back to PRC jurisdiction. Because they were developed by foreign powers with their own legal institutions and police and customs and all that, PRC lets them continue to operate independently of the PRC government on domestic issues. They have their own legislatures and courts but aren't allowed to conduct diplomacy with other nations or have their own military.

PRC says all three of those places are part of their territory. Taiwan is an independent state which just doesn't have official recognition. Hong Kong and Macau are almost the same thing, but there are Chinese military units stationed there and they only have authority on matters within their borders.