For some time I have been confronted with ^C and the like, well, right now I was wondering and finally looked it up. It is officially called the Caret Notation.
Furthermore you can use
cat -v [FILE]to make cat output Control Codes in Caret Notation for a bit of readability of binary files.
Wikipedia has some more articles on the topic: C0 and C1 control codes and Control code.
For instance, did you know that Control subtracts 64 from the parameter character (uppercase) ASCII value, which for ^C (C=67) results in End of text(=3).
