The global object in JavaScript is a shared container that holds variables, functions, and built-in features accessible from anywhere in your code. It's accessed by different names depending on the environment (window in browsers, global in Node.js, self in web workers), but `globalThis` provides a consistent reference across all platforms. Variables declared with `var` become properties of the global object except for `let` and `const`. Modern JavaScript development generally favors modules and proper scoping instead of global variables for cleaner, more maintainable code. The global object is powerful but requires careful handling to avoid pitfalls like name collisions, global clutter, accidental globals, breaking encapsulation, security vulnerabilities, cross-environment problems, and debugging challenges. Best practices include using functions and modules as containers, declaring variables properly, creating a single namespace, leveraging ES6+ modules, keeping sensitive data private, using linting tools, testing for global leaks, and implementing organized access through systems like Strapi role-based access control. The global object can be valuable in scenarios like app configuration settings, communication between scripts, third-party library integration, and callbacks for dynamic scripts, but modern development generally favors more modular approaches when possible.