WATCH: Emotional Ellen celebrates 20 years since 'coming out' episode

Television presenter Ellen DeGeneres is celebrating 20 years since her sitcom Ellen's famous coming out episode.

The 59-year-old invited Oprah Winfrey and her Ellen co-star Laura Dern onto her talk show this week, as she admitted coming clean about her sexuality was the "hardest thing" she has ever done.

"It was the hardest thing that I ever had to do in my life and I would not change one moment of it because it led me to be exactly where I am today – standing in front of all of you, which is a joy," the wife of Portia de Rossi said.

"And the fact that all of you and everyone at home is watching me and willing to accept me into your homes every day when no one thought that would ever happen again, it means the world to me."

Also speaking about the episode of her sitcom in which she "came out", Ellen said: "It was called ‘The Puppy Episode’ because we wanted to keep it a secret until it aired and because ‘Ellen Throws Her Career Away’ seemed too on the nose…

"Actually, the real reason we called it ‘The Puppy Episode’ is ’cause when the writers told the executives that they wanted me to come out because my character needed to be in a relationship after four years of not being in a relationship, someone at the studio said, ‘Well, get her a puppy. She’s not coming out.’ And so, we called it ‘The Puppy Episode'."

Ellen's sitcom was cancelled in 1998, and then three years later NBC picked up her now successful talk show and gave the star a new sense of confidence in herself.

She tied the knot with Australian actress Portia de Rossi in 2008.

Watch the clip above to see Ellen and Oprah chat about what's happened in those two decades since her coming out.

Want more celebrity, entertainment and lifestyle news? Follow Be on Facebook,Twitter, Pinterest, and Instagram