What does the 'this' keyword refer to in a regular function?

In a regular function, when the 'this' keyword is used, it refers to the global object, which is the context in which the function is invoked, unless the function is called as a method of an object. In the context of a browser environment, the global object is typically the window object. Therefore, when a regular function is not attached to an object and is invoked directly, such as myFunction(), 'this' will point to the global object.

This is different from methods defined on an object, where 'this' would refer to the object the method is called on. The behavior of 'this' can also change in strict mode, where it would be undefined instead of referring to the global object if the function is called as a regular function.

Understanding the behavior of 'this' in various contexts is crucial for mastering JavaScript, as it significantly affects how functions and methods interact with their surrounding state.