Encapsulation

The grouping of related items into one unit.

• One of the basic concepts of OO.
• Attributes and behaviors are encapsulated to create objects.
• OO modeling is close to how we perceive the world.
• Implementation details are hidden from the outside world. We all know how to use a phone, few of us care how it works.
• The packaging of operations and attributes representing state into an object type so that state is accessible or modifiable only through the objects' interface
• Encapsulation lets builders of objects reuse already-existing objects, and if those objects have already been well-tested, much larger and more complex systems can be created.