"Modeling Principle: Models are not right or wrong; they are more or less useful."
"Often youll see the same three or four data items together in lots of places: fields in a couple of classes, parameters in many method signatures. Bunches of data that hang around together really ought to be made into their own objects."
"Refactoring (noun): a change made to the internal structure of software to make it easier to understand and cheaper to modify without changing the observable behavior of the software. To refactor (verb): to restructure software by applying a series of refactorings without changing the observable behavior of the software."
"Comprehensiveness is the enemy of comprehensibility"
"People also underestimate the time they spend debugging. They underestimate how much time they can spend chasing a long bug. With testing, I know straight away when I added a bug. That lets me fix the bug immediately before it can crawl off and hide. There are few things more frustrating or time-wasting than debugging. Wouldnt it be a hell of a lot quicker if we just didnt create the bugs in the first place?"
"Often designers do complicated things that improve the capacity on a particular hardware platform when it might actually be cheaper to buy more hardware."
"Refactoring is a disciplined technique for restructuring an existing body of code, altering its internal structure without changing its external behavior. Its heart is a series of small behavior preserving transformations. Each transformation (called a refactoring) does little, but a sequence of transformations can produce a significant restructuring. Since each refactoring is small, its less likely to go wrong. The system is also kept fully working after each small refactoring, reducing the chances that a system can get seriously broken during the restructuring."