What is the relation between Classes and Objects.Class is a definition, while object is a instance of the class created
What is the relation between Classes and Objects

Class is a definition, while object is a instance of the class created. 
class is like a blueprint/template in OOPs, and this template is used to create objects.The collection of properties & behavior of an object is also called as class.
A class contains  properties, fields, data members, attributes.


Example:

Car is an object , cars is a class
            public class cars
            {
                  //
            }


According to the sample given below we can say that the cars object, named object_car, has created out of the cars class.

               cars object_car = new cars();

object is an instance of a class.An object is an entity that has attributes, behavior, and identity. Objects are members of a class.
Objects are accessed, created or deleted during program run-time.

Declaration of an Object in OOPs
ClassName objectName=new ClassName();
Example:
          Car objCar= new Car();



Attribute in OOPs: Attributes define the characteristics of a class. In Class Program attribute can be a string or it can be a integer. 
Behavior in OOPS:  Every object has behavior.
Identity in OOPS:  Each time an object is created the object identity is been defined.