State, Behavior, Class, Object, Action, and Activity

Class is a general template used to define and create specific instances. Every class contains object used to store the information because of its attributes and operations/methods.

Object is an instantiation of a class and every object is with a class. Object is an essential element which is used capture the information.

State a set of values that describes an object status at specific intervals of time. State is represented as rectangle with rounded corners. Arriving, pending, completed are the examples of state.

Action is the process that cannot be interrupted and it is associate with the transaction occurs when the object moves from one state to another state.

Activity is the process that can be interrupted and it takes long time to complete. Activities can be started and stopped by using the action.

Behavior is the process that the object can perform. Sometimes, behaviors are described by operations.