"Some" and "any" refer to an indefinite quantity.
In general, "some" is used in affirmative sentences and "any" in negatives and interrogatives.
It is more polite to make an offer with "some".
Also the use of "some" indicates that we expect an affirmative response.
- "Have you got any money?" "No, I haven't got any. But, we can borrow some from Hazel."
- "You look thirsty. Would you like some water?"
- "You look terrible. Did you get any sleep last night?"
"Any" also means every (of more than two), no matter which.
- If you have any questions whatsoever we'll be more than happy to answer them during the break.