In C++, what are access modifiers?

In C++, access modifiers are keywords used to specify the visibility and accessibility of a class or structure's members, such as attributes and methods. These modifiers are crucial for achieving encapsulation, which is a fundamental principle of object-oriented programming (OOP) that helps protect sensitive data by controlling access to it.

C++ supports three main access modifiers:

1. Public (public): Members declared as public are accessible from anywhere in the program. They are typically used for the interface of a class, allowing interaction with private data through public methods.

2. Protected (protected): Members declared as protected are accessible within the defining class and derived classes. This is useful for inheritance, where child classes can access and reuse members from the parent class.

3. Private (private): Members declared as private can only be accessed within the defining class or structure. They hide implementation details and prevent unauthorized access or modification of sensitive data.

Here is a summary of how these modifiers affect accessibility:

By default, members of a class are private if no access modifier is specified, while members of a struct are public by default134.