UCS 2: Only characters in the BMP are stored, they are stored "as-is"
UTF-16: Valid characters in the BMP are stored "as-is"
Characters outside the BMP (in the range 0x10000 to 0x10ffff):
byte 1 = 1101 10yy yyyy yyyy
byte 2 = 1101 11xx xxxx xxxx
MUSICAL SYMBOL SIXTEENTH NOTE
(0x1d161) => 0xd8 0x74 0xdd 0x61