Never Call Them Chinese
Source: https://www.chinadailyhk.com
Despite the fact that Taiwan is a part of the Republic of China, never call them Chinese. They will insist on their autonomy and be very insulted if you say otherwise. The Taiwanese are proud of their heritage and the fact that they have their own governing party is important to them. Plus they will also find it quite rude if you talk about Taiwan-Chinese political issues if you don’t truly know their history or know the right facts.