Unicode

http://stackoverflow.com/questions/3951722/whats-the-difference-between-unicode-and-utf8

http://stackoverflow.com/questions/4655250/difference-between-utf-8-and-utf-16

http://www.differencebetween.net/technology/difference-between-unicode-and-utf-8/

https://en.wikipedia.org/wiki/Byte_order_mark

http://www.differencebetween.net/technology/software-technology/difference-between-ucs-2-and-utf-16/

http://hackipedia.org/Character%20sets/Unicode,%20UTF%20and%20UCS%20encodings/UCS-2.htm

Vim supports (amongst others):

Windows 1252 is a character encoding of the Latin alphabet, and the default character set in English Windows. An extension of ISO 8859-1.

Mac's TextEdit "Western (Windows Latin 1)" is UTF-8 without a BOM.

Windows 7's Notepad saves in the following encodings:

https://en.wikipedia.org/wiki/UTF-16