A comprehensive collection of explanations and implementations covering algorithms, data structures, mathematics, and techniques commonly used in competitive programming.

The formal specification defining the ECMAScript programming language, including JavaScript's syntax, semantics, built-in objects, execution model, and language behavior.

A collection of Java implementations and explanations of common software design patterns, providing practical examples of object-oriented design principles and reusable programming solutions.

A globally accessible knowledge base mapping real-world adversary behavior into tactics, techniques, and procedures used to understand and analyze cyber threats.