A character literal is a pair of single quotes enclosing either a single ISO-Latin-1 printing character (excluding single quote) or an escape sequence. The type of a character literal is CHAR.
A text literal is a pair of double quotes enclosing a sequence of ISO-Latin-1 printing characters (excluding double quote) and escape sequences. The type of a text literal is TEXT.
Here are the legal escape sequences and the characters they denote:
\n newline (linefeed) \f form feed
\t tab \\ backslash
\r carriage return \" double quote
\' single quote \nnn char with code 8_nnn
A \ followed by exactly three octal digits specifies the character
whose code is that octal value. A \ that is not a part
of one of these escape sequences is a static error.
For example, 'a' and '\'' are valid character literals, ''' is not; "" and "Don't\n" are valid text literals, """ is not.