(A) little / (A) few

(a) little + uncountable noun:

I have a little money in my pocket (some, but not much).
There's little food in the fridge (nearly nothing).

(a) few + plural countable noun:

I have a few coins in my pocket (some, but not many).
There are few people in the park (nearly nobody).

A little & A few express positive ideas:

I have a little money (I'm not poor).
I have a few friends (I'm not alone).

Little & Few express negative ideas:

I have little money (I'm not rich).
I have few friends (I'd like to have more friends).