International Domain Names (IDN), are web addresses that are displayed in non-ASCII character sets or alphabets in the Internet Explorer Address bar. This allows websites to display their addresses using their native language and character set.
For security purposes, Internet Explorer will display International Domain Name web addresses in a standard ASCII text encoding by default.
The standard text encoding is used because it's possible for letters and symbols in some languages to be used to impersonate English language websites for phishing scams. If you browse to a website with a native language address, but you don't have the language available, the Information bar will display the message "This web address contains letters or symbols that cannot be displayed with the current language settings. Click here for options."
If you frequently visit websites that are written in languages that you cannot currently view, you might want to install additional languages in Internet Explorer. When the message appears on the Information bar, click Change language settings, and follow the instructions.