The Taiwan official language is Chinese. There is actually 3 different dialects of Chinese spoken in Taiwan. The main dialect used is Mandarin. It is estimated that 900 million people in the world (1/4 of the world population) speak a dialect of Chinese. Mandarin is spoken by at least half of the people in China as their mother tongue and is the official language of Taiwan and Mainland China.
Chinese is said to be one of the hardest languages to learn if not the hardest. Most of the sounds can be found in the English languages, but the biggest difference is the variation of tones. There are four different tones. The Chart below helps explain how the tones work:
You can pronounce the same sound, but depending on the pitch of your voice, can completely change the meaning of the word. The picture below demonstrates the different meanings of words by the tone you use.
The written language is also very difficult. They do not use a alphabet like we do but symbols. Education Chinese people can recognize about 6,000-7,000 characters. To read a newspaper you need to know about 2,000-3,000 characters. There are over 40,000 characters, including obscure, variant, rare, and archaic characters, however less then a quarter of these are still commonly used today.