About Punycode
Punycode is a special encoding used to represent Unicode characters in ASCII-only domain names. It allows internationalized domain names (IDN) to work with the existing DNS infrastructure.
Examples:
测试→xn--0zwm56dhttp://测试.com→http://xn--0zwm56d.comтест→xn--e1aybcтест.com→xn--e1aybc.commünchen→xn--mnchen-3ya