When to use "Well" or "Good" [duplicate]

Possible Duplicate:
Why do so many people get this wrong? “How are you? / I'm well.”

How would you answer the question "How are you?"

I'm well.

or

I'm good.

I notice that in American English, the latter is normally used, but I feel that the former is grammatically correct.

Same goes for questions like "How did it go?" Can one answer "It went well," or "It went good."

Which is correct?

One key difference is that "well" can be an adverb and "good" cannot, at least not formally. This is why "it went good" is grammatically incorrect. However good is so often used as a synonym for well in vernacular English that dictionaries may mention its nonstandard equivilance.

To answer your first question, it's usually preferred to say "I am well" in formal English because it specificially means "I am in good health" whereas "I am good" doesn't have that specific association. "I am good" is grammatically correct though.

I usually say "I am well", meaning "I am in good health", with the caveat that most people to whom I say it regard me as being perhaps overly formal. "I'm good", to me, connotes other possible meanings, such as "I'm quite competent", but others' mileage may vary.

I would avoid "it went good" as ungrammatical.

Both are correct. When you give either response, there are words that aren't said that are understood.

eg.

I am (feeling) well.

or

I am (in) good (spirits/health.)

"It went well" is correct, well is an adverb modifying went. "It went good" is incorrect, as good is not an adverb.