It depends on the topic of the book, of course, but some of the best computer science books I've read were written in the 70s and 80s (SICP, Dragon Book, etc.).

It depends on the topic of the book, of course, but some of the best computer science books I've read were written in the 70s and 80s (SICP, Dragon Book, etc.). The C programming language, one of the most popular languages in use today, has not changed much since the 80s.