Data structure: specialized format for organizing and storing data to be used efficiently. Office hours: wednesday 14:00 - 15:00 at me 4239. Oop views a program as a collection of objects. Used to enforce the walls of an adt. Combines an adt"s data with its method to form an object. Hides the implementation details of the adt from the programmer who uses it. A new data type whose instances are objects. All members in a class are private, unless the programmer designates them as public. Destroys objects that a program no longer references. Finalize method for objects for talks other than memory deallocation. Allocate memory for an object and can initialize the object"s data. A class can have more than one constructor. Typically, initializes data fields to values the class implementation chooses. Compiler - generated default constructor: generated by the compiler if no constructor is included in a class.