How can we define a Functional interface in Java 8?
What is a Functional interface in Java 8?

Please tell me if those questions are the same.
A: no

Is 0 a natural number?
Why is 0 a whole number but not a natural number?

Please tell me if those questions are the same.
A: no

Why Most of the professors or lecturers dont attend teaching in universities?
Has Dr. Who ever been caught on his hypocrisy and double standards?

Please tell me if those questions are the same.
A:
no