What is inner class?

Question

Please tell me, what is inner class?

Answer 1

A class within another class is known as nested class. There
are two type of nested class static nested class and non
static nested class.The static nested class did'nt access
its enclosed member function directly, where an non static
nested class can directly access. the non static nested
class is known as inner class.

Answer 2

A class defined inside another one is called an inner class