Well, dictionary.com defines faith as...

1. confidence or trust in a person or thing: faith in another's ability. 
2. belief that is not based on proof: He had faith that the hypothesis would be substantiated by fact. 
3. belief in God or in the doctrines or teachings of religion: the firm faith of the Pilgrims. 
4. belief in anything, as a code of ethics, standards of merit, etc.: to be of the same faith with someone concerning honesty. 
5. a system of religious belief: the Christian faith; the Jewish faith. 
6. the obligation of loyalty or fidelity to a person, promise, engagement, etc.: Failure to appear would be breaking faith. 
7. the observance of this obligation; fidelity to one's promise, oath, allegiance, etc.: He was the only one who proved his faith during our recent troubles. 
8. Christian Theology. the trust in God and in His promises as made through Christ and the Scriptures by which humans are justified or saved.
—Idiom
9. in faith, in truth; indeed: In faith, he is a fine lad. 

... which certainly is a nice compilation of definitions. But here's my question. Can't all these instances of the word "faith" be used equally with the world "belief"? Some of the definitions even use "belief" in them! So... what's the difference?

Hm, let's try an example... the phrase "I have faith in God." Ok, what is this faith that you have in God? Is it interchangably used for belief? If so, how come so few people use "belief"? Say you're in a tough situation, and you say "I have faith that God will pull through for us." Why don't most people say "I believe that God will pull through for us."? It's always about faith, yet there doesn't seem to be a satisfying definition for faith... ambiguous at best.

Possibly the best out of that list in definition #2, "belief not based on proof." Yet... and this is nitpicking, of course... but why do they use the more science-y example than the religion example? "faith in hypothesis" isn't the same as "faith in God"? I'd think if anything a hypothesis has more proof than a mystical being, but there's no specifics, so it's hard to say. But, say you have proof. Let's use God again. For you, there is absolute proof, no doubt in your mind, had a magical experience that yes God does exist. So why do you still have faith in God? If you have the proof, how can you have a belief not based on proof?

This may be getting into the connotations of words, which is always tricky. But how do you explain faith?It's a strange word that I try to avoid using whenever possible. Maybe it's hard for me because I wasn't raised in a religious household, so the only use of the word faith I ever heard was "I have faith you'll do good on the test tomorrow" from my parents. But even in that case! Wouldn't that the faith that I'll do good be based on how well I've done on other tests? So if there's proof, why use the word faith!

On a side note, does the word faith exist in other languages?

Heh, I've really been getting into this philosophy stuff lately. This stems from my professor's inability to understand the word faith, too. Of course, I had it all figured out until he came along and brought it up in class. *eyeroll* But seriously, if anybody can help me understand this tricky stuff, I'd appreciate it :)