Deleted code is debugged code.

Incorrect documentation is often worse than no documentation.

When working on a problem, think only how to solve it. If the solution is not simple and has no inner beauty such as art, it is wrong.

Hofstadter's Law: It always takes longer than you expect, even when you take into account Hofstadter's law.

Unix has retarded OS research by 10 years and linux has retarded it by 20.