What does data encapsulation achieve in software design?

Data encapsulation in software design is fundamental to object-oriented programming and is achieved by restricting access to the internal state of an object. This principle allows developers to hide the intricate details and implementations of a class while exposing only what is necessary through public methods.

By encapsulating data, it ensures that the internal workings of an object can be modified without affecting other parts of the program that rely on the object's public interface. This promotes maintainability and flexibility since changes to the internal state can be made safely, minimizing the risk of unintended consequences in the rest of the code. Additionally, encapsulation helps enforce data integrity by controlling how the data can be accessed and modified, thereby preventing unauthorized access or modifications from outside the defined interface.

In contrast, exposing all internal states or attributes of an object can lead to dependencies that make the software more fragile and harder to maintain. While reducing memory usage and increasing execution speed are important considerations in software development, they are not directly achieved through data encapsulation itself, making them less relevant to the core purpose of encapsulation.