What does it mean to be a great journalist?

Talking from the wide perspective, nowadays, almost everyone has an opportunity to try to be a non-professional journalist and it looks like easy, quickly and interesting hobby when sometimes you can even win fame. BUT such media, when everyone can practise their skills of journalism, isn't professional and worth to trust. Traditional journalists make mistakes as well. So, what does it mean today to be a great journalist?

We can mention Carl Berstein, a professional and experienced American investigate journalist and author, who gave several proper tips about being a great journalist.