This repository is an educational resource focused on teaching the Gang of Four (GoF) design patterns through comprehensive explanations, code examples, and diagrams. It covers creational, structural, and behavioral patterns, with each pattern accompanied by detailed markdown documentation, visual diagrams, and runnable code samples in both Java and Kotlin. The project structure organizes content by pattern type, making it easy to locate and study specific patterns. The code examples demonstrate practical implementations of each pattern in context-specific scenarios, such as a banking system for the Command pattern, a notification system for the Decorator pattern, and a file system for the Composite pattern. While the build configuration defaults to running a Singleton demo, each pattern includes independent main functions or demo classes that can be executed separately. The repository also features automated workflows for building and deploying the documentation via GitHub Pages. Despite some maintenance challenges like duplicate documentation files (marked for removal in a future version) and the coexistence of Java and Kotlin examples, the project shows active maintenance through contribution guidelines, regular updates, and a clear migration path toward consolidating documentation. The examples are well-crafted, self-contained, and illustrate core object-oriented design principles effectively, making them valuable for both learning and reference purposes.