[a play on ‘Coke Classic’] The C programming language as defined in the first edition of K&R, with some small additions. It is also known as ‘K&R C’. The name came into use while C was being standardized by the ANSI X3J11 committee. Also ‘C Classic’.
An analogous construction is sometimes applied elsewhere: thus, ‘X Classic’, where X = Star Trek (referring to the original TV series) or X = PC (referring to IBM's ISA-bus machines as opposed to the PS/2 series). This construction is especially used of product series in which the newer versions are considered serious losers relative to the older ones.