I know that C strings are char[] with a '\0' in the last element. But how are the chars encoded?
Update: I found this cool link which talks about many other programming languages and their encoding conventions: Link
All the standard says on the matter is that you get at least the 52 upper- and lower-case latin alphabet characters, the digits 0 to 9, the symbols ! " # % & ' ( ) * + , - . / : ; < = > ? [ \ ] ^ _ { | } ~, and the space character, and control characters representing horizontal tab, vertical tab, form feed, alert, backspace, carriage return, and new line.
The only thing it says about numeric encoding is that all of the above fits in one byte, and that the value of each digit after zero is one greater that the value of the previous one.
The actual encoding is probably inherited from your locale settings. Probably something ASCII-compatible.