Question

black hole was first detected in which year

Answer 1

In 1916 black hole was predicted by Albert Einstein in General Theory of Relativity.  In 1971 Cygnus X-1 star, was first object to be recognized  as a black hole.

Black hole is a region of space having a gravitational field so intense that no matter or radiation can escape. 

There are three types of black hole :

1). Super massive black hole

2). Stellar black hole

3). Intermediate black hole