system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: What's the difference between Republic of China and People's Republic of China?

I understand that Republic of China is more capitalist, and People's Republic of China is communist.  I also know that Republic of China is based out of Taiwan.  That's it though, can someone help with the rest?
gpt
Before WW2, a nationalist party called the Kuomintang was in control of China. Back then all of China was the Republic of China. But following WW2, there was a communist revolution, and the People's Republic of China was established.

The Kuomintang retreated to Taiwan where they continued to run the government of the Republic of China, which they claimed was still the legitimate government of all of China.

The UN continued to recognise them as China's government until the 1970s, when the PRC was invited to take their place as China's representatives. The PRC has a policy that they will not have diplomatic relations with any country which recognises the ROC as a legitimate state, which is why even countries like the USA *technically* don't recognise Taiwan as a country. Although there are a few countries which do.

Taiwan has now evolved into a modern democratic country. A lot of people in Taiwan don't really think it's the legitimate government of mainland China any more, and would like to drop their claims to it. 

But officially declaring Taiwan as an independent country would cause problems, even though that's exactly what it is in practice. The PRC sees Taiwan as a rogue province, an integral part of China which is currently defying the legitimate government. And they have threatened to take military action if Taiwan officially declares independence.