Robert Downey Jr as Tony Stark
Robert Downey Jr as Tony StarkFacebook / Iron Man

"Iron Man" and his alter ego Tony Stark is probably one of the most well-known name among Marvel fans. The character garnered worldwide recognition after Robert Downey Jr portrayed it in 2008's "Iron Man" based on Marvel's comic book character of the same name.

Since then, Downey Jr has portrayed Iron Man in several other Marvel Cinematic Universe (MCU) movies like "Iron Man 2" (2010), "The Avengers" (2012), "Iron Man 3" (2013) and "Avengers: Age of Ultron" (2015). He is all set to reprise the role of Iron Man and Tony Stark in the upcoming "Captain America: Civil War" that is scheduled to release May 6 in North America.

Besides playing Iron Man, Downey Jr has also acted in critically acclaimed movies like "Chaplin" (1992) and "Kiss Kiss Bang Bang" (2005). As the actor celebrates his 51st birthday, here are some of his most popular quotes:

"Nothing's a break for me. Not even the breaks are breaks."

"The lesson is that you can still make mistakes and be forgiven."

"But I think 'Kiss Kiss, Bang Bang' really got that thing where, if a movie reads really funny and then has some dramatic or violent or sinister stuff in it, you can't forget that primarily it has to be even funnier than you read it or that other stuff."

"I've noticed that worrying is like praying for what you don't want to happen."

"I think that the power is the principle. The principle of moving forward, as though you have the confidence to move forward, eventually gives you confidence when you look back and see what you've done."

"I think that we all do heroic things, but hero is not a noun, it's a verb."

"I always think part of success is being able to replicate results, taking what is interesting or viable about yourself as a professional person and seeing if you bring it into different situations with similar results."

Source: Brainy Quotes