Internationalized Domain Names (IDNs) are a way to incorporate non-ASCII characters into domain names. Traditional domain names are limited to ASCII characters, which include the English alphabet, digits, and a few special symbols. However, this restricts the use of domain names in many languages around the world.
IDNs solve this problem by allowing domain names to be represented in various scripts or alphabets, including non-Latin scripts or Latin-based characters with diacritics or ligatures. These writing systems are encoded by computers in multibyte Unicode. IDNs are stored in the Domain Name System (DNS) as ASCII strings using Punycode transcription.
However, even though IDNs allow for a wider range of characters, they still adhere to certain restrictions to ensure consistency and prevent confusion. For example, IDNs must comply with the IDNA2008 protocol, which specifies how domain names are converted into ASCII for storage in the DNS.
Moreover, while IDNs can be beneficial for reaching audiences in different languages or regions, they can also introduce complexity. For instance, the same domain name can appear differently in different scripts, leading to potential confusion and misinterpretation. Additionally, the use of special characters in IDNs can present challenges for user typing and recognition, similar to traditional domain names.
In summary, while IDNs expand the range of characters that can be used in domain names, they also introduce additional complexities and potential issues, particularly around user experience and recognition.