When the DNS (Domain Name System) first entered into operation in 1983, only the characters in the Latin alphabet were allowed to be used. With this system, although the characters of different alphabets could have a place in the DNS, web browsers and e-mail clients were not supporting such usage. By way of IDN (Internationalized Domain Name), that was first introduced in 2000, characters in non-Latin alphabets began to be available to use. Thereby, domains in almost all languages started to be registered. Until today 4 million IDNs were registered.
Read More: https://blog.dofo.com/internationalized-domain-names/