The authors of "Design Patterns" didn't create anything new, they just documented common patterns used in the industry and gave them a name. So, when you say "I

The authors of "Design Patterns" didn't create anything new, they just documented common patterns used in the industry and gave them a name. So, when you say "I used X pattern here", I can have a high level architecture of the code in my mind when navigating it and how it's supposed to work. You should read the title as "Design Patterns for Java". You can try to implement the patterns in other languages and it may work but, if it doesn't, that doesn't mean the book is useless, it just doesn't fit your language of choice. I believe someone would've written a book similar to "Design Patterns" at some point in time. It just happened to be the GoF. You can say whatever you want, but today we all use patterns to talk about software. It may or may not be thanks to the book. We'll never know.