Java OOPS Keypoints

Object  -
 object is a software bundle of related state and behaviour.
 software object are often used to model the real world object that we find in everyday life.

class
 class is a blueprint or prototype from which object or created.

Inheritance
 How the class inherit the state and behaviour of super class.

Interface:
 Interface is a contract between class and outside world.
 when class implement an interface, it promises to provide the behaviour published by that interface.

package
  package is a placing class and interface in logical manner.
  it manage large software project if their class and interface into package.