Always prefix a Unicode plain text file with a byte order mark

This comes from the MSDN page entitled “Using Byte Order Marks”.

Byte order mark Description
EF BB BF UTF-8
FF FE UTF-16, little endian
FE FF UTF-16, big endian
FF FE 00 00 UTF-32, little endian
00 00 FE FF UTF-32, big-endian