What exactly is the "American Dream"?

As a presidential candidate in 1928, Herbert Hoover used the campaign slogan: "A chicken in every pot and a car in every garage".

I always thought that was the American Dream; even if I did not vote in that election.

There are so many great answers I am not sure I could contribute anything more. I remember when I was young and growing up it was the Horatio Alger type thing. Growing from nothing to a successful tycoon. As I grew older "successful" changed to mean more than just financial security but to include a family, and health and security, which I think for my generation was typical.
However as I look at the kids today it appears they are being told "success" is bad. Wealth is evil. They expect to be taken care of. It is their "right" not so much their responsibility, but then I read the entries here and I gain a lot of hope for a bright future. I have achieved the American dream, in that I am secure, happy and have my health, have a wonderful wife and family. God had truly blessed us all. The American Dream appears to be alive and well

You get to determine what you are going to be, and if you will succeed or fail, regardless of whether you have "high" or "low" birth. No one is supposed to be your master.

Great timing to ask this question. It's different for everyone, but I think of it as freedom unrestricted by big government and the opportunity to live a life you desire with your family through: faith in any religion, honesty, hard work, and dedication.

There isn't really an American dream any more is there? Growing up it was always owning your own home and having a good job and family. Now I don't believe there is the American dream any more.