Unicode is a character set that is capable of representing all written languages.
The ANSI character set, which employs a single byte (8 bits) to represent each character, can represent up to 28 = 256 characters only. This is enough for Western languages, but it is insufficient for languages such as Chinese. In contrast, the Unicode character set employs two bytes (16 bits) per character, so it can represent a total of 216 = 65,536 characters - enough for every language in the world plus punctuation and standard mathematical symbols.
Unicode is the native character encoding for file and object names in Microsoft Windows NT and Windows 2000. The Win32 subsystem converts American National Standards Institute (ANSI) strings to Unicode before any string operations are performed on them. Filenames are represented in NTFS file system using Unicode.
If you create a logon script in Windows NT by using Notepad, do not select the Save As Unicode check box when you save the logon script, or it will fail to execute properly.