Why does every object in Java implicitly extend java.lang.Object class?

Question

I have been programming in Java for quite some time, but when I tried to explain what an java.lang.Object class is to a friend, I could not come up with more th

Answer 1

Quoting Head first Java 2nd edition:

Without a common superclass for everything in Java, there’d be no way for the developers of Java to create classes with methods that could take your custom types... types they never knew about when they wrote the ArrayList class.

Which essentially explains the need of a generic predefined class type in Java, which can be used to implement the different features provided by the language.