INTRODUCTION

The world we live in is composed of objects. Everything that we see is an example of object. We ourselves are examples of objects. The chair you are sitting on is another example of objects. The car, your father drives is also an example of object. The pets in your house are also objects. The list is endless.

Aren’t you wondering what this objects all about is? Why are we referring to everything as an object? Well, answer to all these questions, you will find in coming lines. This chapter is dedicated to the discussion of concepts of objects. Let us begin with what exactly an object is.

What is an object?

An object, in real world, can be one of the following:

·        Anything that is visible or tangible.

·        Something that may be apprehended intellectually.

·        Something towards which one can direct action or thought

If we study all things meeting above criteria of being objects , we can say that each of these has a unique identity , some definitive state or characteristics and some behavior .For instances , we can say that an ”ORANGE” is an object . Its characteristics are: it is spherical shaped; its color is orange etc. Its behavior is: it is citrus in nature and it tastes sweet sour. Similarly, we can say that your chair is also an object. Its characteristics are: it has four legs, a back, may or may not have arms. Its behavior is: it let you sit on it. With this description can you suggest some more object examples?

Keep thinking, in the mean time, we define object as follows:

An object can be thought of as an entity having specific identity, specific characteristics and specific behavior.

OR

Java is on object oriented programming language. An object is a self contained element of computer program that represent a related group of feature and is design to do specific task. Objects are also called instances.

      Every object has the following inbuilt characteristics, which we had already discussed above:-

            a)      Identity :- it is the name by which an object is recognize. E.g. pen ,box, chair etc.

            b)      State :- the object may be in any state that is processed or unprocessed. For example the computer may be in any of the following state; on state ; off state; out of order.

             c)      Behaviour :- this refers that what an object is capable of doing.

NOTE: The state of an object is represented through the values/attributes of its characteristics at a given point of time.