What is encapsulation in programming?

Encapsulation in programming is fundamentally about restricting access to certain components of an object while still allowing easy interaction through defined interfaces. This principle is one of the cornerstones of object-oriented programming (OOP).

It serves multiple purposes, including enhancing data integrity, as it helps prevent unintended interference and misuse of data. By encapsulating data, programmers can hide the internal representation of an object from the outside world, exposing only the necessary parts through public methods. This allows changes to the internal structure without affecting external code that relies on the object, promoting maintainability.

For example, in a class representing a bank account, sensitive details like the balance should not be directly accessible from outside the class. Instead, methods can be provided to facilitate controlled access (like deposit and withdrawal methods) while keeping the internal state secure.

The other options do not accurately represent encapsulation. While performance enhancement, multiple inheritance, and writing reusable code are important concepts in programming, they do not define the protective and modular nature encapsulation brings to object-oriented design.