Using Patterns in Practice

(1) When you start designing a system, it can be difficult to know in advance if you will need a particular pattern; pattern use often involves developing a design, experiencing a problem, and then recognizing that a pattern can be applied

(2) Patterns are most effective when the designer can focus on the 23 general-purpose patterns from the Gang of Four's original book

(3) Patterns have become a vocabulary for talking about software design - you can explain your design by describing the patterns you have used

(4) If your problem is different from those addressed by the well-known patterns, you may find it difficult to find an appropriate pattern among the hundreds that have been proposed

Explanation

True statements: it is hard to know in advance which patterns you'll need; the 23 Gang of Four patterns are the most focused and applicable starting point; patterns are a design vocabulary; finding an appropriate pattern among hundreds can be hard for unusual problems. False: inexperienced programmers do NOT find it easy - you need experience to recognize when a pattern applies. This is a key limitation of patterns in practice.