If you had done something twice, you are likely to do it again.

The most effective debugging tool is still careful thought, coupled with judiciously placed print statements.

Do what you think is interesting, do something that you think is fun and worthwhile, because otherwise you won't do it well anyway.

Another effective [debugging] technique is to explain your code to someone else. This will often cause you to explain the bug to yourself. Sometimes it takes no more than a few sentences, followed by an embarrassed "Never mind, I see what's wrong. Sorry to bother you." This works remarkably well; you can even use non-programmers as listeners. One university computer center kept a teddy bear near the help desk. Students with mysterious bugs were required to explain them to the bear before they could speak to a human counselor.

Controlling complexity is the essence of computer programming.

If you're as clever as you can be when you write it, how will you ever debug it?

As we said in the preface to the first edition, C "wears well as one's experience with it grows." With a decade more experience, we still feel that way.