Object oriented programming consists of developing and implementing application systems as sets of interacting software objects.

A software object, as most objects in everyday life, such as an automobile, has a unique identity and certain attributes and behaviors. The automobile has a unique identity, its serial number; it has many attributes such as color, number of doors, and weight. It also has behaviors, such as forward, reverse, accelerate, shift, and the like. Software objects are used to model real world objects and as such they abstract the key concepts of the real world object in software. A software object used to model an automobile would for example, have a unique identity, and attributes such as color, weight, and length, as well as behaviors such as forward and reverse.

Software objects can be used to model any of the concepts germane to a given problem domain. For example, they can represent bank accounts, employees, parts, processes, programs, fields, files, structures and the like.

Therefore, we can say a software object is an entity that has a unique identity, specific data values, and specific behaviors or program code. The program code is organized into small modules. In object oriented terminology these modules are called methods. Data is encapsulated within each object and can only be accessed by using one or more of the object’s methods.