HTML pages have been designed with the help of experts so that they may be written in many different languages with different characters and can still be transported easily around the world without problems. This has already been accomplished several decades ago. 
International characters, such as those of the Arabic, Chinese, Japanese and other languages as well as text direction, punctuation and other world language characteristics can be displayed correctly.
This support of diverse human languages within a document aids search engines finding content in these languages, assists in better text-to-speech conversion and helps with many other features.