A penis expert claims there are four different types of male genitalia.

According to BuzzFeed.com, Dr. Shusterman, a urologic surgeon, said the first was named ‘The Big Head’ and is when the head of the penis appears to be thicker and bigger than the rest.

The second is ‘the Big Shaft’ where the head of the penis is smaller and the penis ends in a slight point.

‘The Curve’ is third and describes penises that slightly curve upwards.

Last on the list is ‘The Bender’, but Dr. Shusterman says if there is an extreme curve on the penis it could be a sign of Peyronie’s disease.