What does the keyword 'this' refer to in JavaScript?

In JavaScript, the keyword 'this' is used to refer to the current context or object from which it is invoked. It is a dynamic reference, meaning that its value can change depending on how a function is called.

When methods are called on an object, 'this' points to that specific object. For example, within an object method, 'this' refers to the object itself, allowing access to its properties and other methods. When using 'this' in a constructor function, it refers to the instance of the object that is being created.

Additionally, in global contexts, 'this' refers to the global object (like the 'window' object in browsers). However, when dealing with strict mode, 'this' can be undefined in certain situations, such as when functions are called as standalone functions, not as methods of an object.

The flexibility of 'this' provides a powerful way to access object properties and methods contextually, making it an essential concept in understanding JavaScript's object-oriented capabilities.