While the first publication of the Gang of Four's Design Patterns: Elements of Reusable Object-Oriented Software was released in October of 1994, I have only been paying attention to design patterns for the last 12 years. Like most experienced developers, when I first started reading about design patterns, I recognized a lot of the patterns because I had already been using them without realizing what they were. I would have to say that in the past 12 years since I first read about design patterns, I have not written a serious application without using at least one of the Gang of Four's design patterns. I will tell you that I am definitely not a design pattern zealot, and if I get into a conversation about design patterns, there are usually only a couple of them that I can name without having to look them up. But one thing that I do remember...
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