What is the significance of the 'this' pointer in C++ classes?

The 'this' pointer is significant in C++ classes because it provides a way for non-static member functions to access the object for which they were called. Specifically, 'this' is an implicit pointer that refers to the invoking object itself. This allows member functions to manipulate the member variables and call other member functions of that specific instance.

Using 'this' is particularly useful when there is ambiguity, such as when function parameters have the same names as class member variables. By using 'this->variableName', a programmer can explicitly specify that they are referring to the member variable of the class rather than the parameter.

In the context of object-oriented programming, 'this' allows methods to work on the instance data of a class, facilitating actions like returning the instance from a member function or implementing method chaining by returning *this. Understanding the role of 'this' is essential for grasping how objects and their methods interact within C++.