As an application developer, you can have a lifelong career without ever knowing what any of the patterns are called or how or when they're used. However, I've found that a good working knowledge of these patterns, as well as those introduced in the developerWorks article "Five common PHP design patterns" (see Resources), allows you to do two things: Enable high-bandwidth conversations and reduce painful lessons.

The patterns they talk about in this "five more" article of the series are:

• Adapter Pattern
• Iterator Pattern
• Decorator Pattern
• Delegate Pattern
• State Pattern

Diagrams are provided for each of them, showing how they flow along with brief code examples (structures really) to show how that transitions over to actual use.