However, if we consider object diagrams then we can have unlimited number of instances, which are unique in nature. To capture a particular system, numbers of class diagrams are limited. In class diagram elements are in abstract form to represent the blue print and in object diagram the elements are in concrete form to represent the real world object. So both diagrams are made of same basic elements but in different form. It implies that an object diagram consists of instances of things used in a class diagram. We have already discussed that an object diagram is an instance of a class diagram. Understand object behaviour and their relationship from practical perspective The purpose of the object diagram can be summarized as − The purpose is to capture the static view of a system at a particular moment. It means the object diagram is closer to the actual system behavior. However, an object diagram represents an instance at a particular moment, which is concrete in nature. The difference is that a class diagram represents an abstract model consisting of classes and their relationships. The purposes of object diagrams are similar to class diagrams. The purpose of a diagram should be understood clearly to implement it practically. Object diagrams are used to render a set of objects and their relationships as an instance. Object diagrams also represent the static view of a system but this static view is a snapshot of the system at a particular moment. The basic concepts are similar for class diagrams and object diagrams. Object diagrams represent an instance of a class diagram. Object diagrams are derived from class diagrams so object diagrams are dependent upon class diagrams.

Interaction diagram