The difference between "little" and "a little" is that: "little" means "almost nothing" - "little water" = "almost no water" "a little" means "there is some but not much" - "a little water" = "there's some water" Basically in the first case the idea is negative, in the 2nd it's positive - the glass is half empty or half full. The same story is with "few" and "a few" but with countable nouns while "little/a little"is used with uncountable nouns. As for "the little", we really need some context as "the" is often contextual.

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