What's the differences between object and object references?

Student s = new Student("Joe",20);
is an object of class Student. Can we say s is an object reference
class Student?


s is not an object, it's a variable which contains a reference to an object.
Objects don't have names, just types and locations in memory (and, of course,
fields and methods). Read your statement as: Create a new Student object in
memory, initializing it with the data sent as arguments to a constructor, and
when created, assign a reference to that object to the Student variable s. s
is a reference or object type variable which may reference a Student object or
an object of any subclass of Student.

Take another statement: int x = s.getValue();

Read this statement as "Go to the object referenced by variable s and execute
its getValue() method. Assign the return from that method to the int variable
x."