90% of the functionality delivered now is better than 100% delivered never.

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

Get the weirdnesses into the data where you can manipulate them easily, and the regularity into the code because regular code is a lot easier to work with

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.

Each new user of a new system uncovers a new class of bugs.

... it is a fundamental principle of testing that you must know in advance the answer each test case is supposed to produce. If you don't, you are not testing; you are experimenting.

Mechanical rules are never a substitute for clarity of thought.