Abstraction is a means of achieving stepwise refinement by suppressing unnecessary details and accentuating relevant details.

Class is an abstract data type that supports inheritance.

Cohesion is the degree of interaction within a module.

Coupling is the degree of interaction between two modules.

Data encapsulation is a data structure together with the actions performed on that data structure.

Encapsulation is the gathering together into one unit of all aspects of the real-world entity modeled by that unit.

Information Hiding is the structuring the design so that the resulting implementation details will be hidden from other modules.

Object is an instance of a class.