"CR" is a single character"CR" is a string containing the two characters C and R followed by the NULL terminator
"\n" is a coded parameter "n" send to the "printf"The backslash inside a string is an escape character and the character following it is interpreted differently.
\n is translated (by the compiler) to the linefeed character
\r is translated to the carriage return character
\t is translated to the horizontal tab character.
\\ is translated to a single backslash character
These and other escaped characters are valid in any C string, not just in printf strings.
So, "\n" is a string consisting of a linefeed character followed by the NULL terminator.
The special character in a printf string is %.