A Little / A Few

The expressions a little and a few mean some.

* If a noun is in singular, we use a little
Example: a little money

* If a noun is in plural, we use a few

Example: a few friends

Countable / Uncountable Nouns

In connection with a little / a few people often speak of countable nouns and uncountable nouns.

Countable nouns have a singular and a plural form. In plural, these nouns can be used with a number (that's why they are called 'countable nouns'). Countable nouns take a few.
Example: 4 friends – a few friends
Uncountable nouns can only be used in singular. These nouns cannot be used with a number (that's why they are called 'uncountable nouns'). Uncountable nouns take a little.

Example: 3 money – a little money

Note: Of course you can count money – but then you would name the currency and say that you have got 3 euro (but not „3 money“).
A Little / A few or Little / Few

It's a difference if you use a little / a few or little / few. Without the article, the words have a limiting or negative meaning.
* a little = some little = hardly any

Example: I need a little money. - I need some money. I need little money. - I need hardly any money.
* a few = some few = hardly any

Example: A few friends visited me. - Some friends visited me. Few friends visited me. - Hardly any friends visited me.

Without the article, little / few sound rather formal. That's why we don't use them very often in everyday English. A negative sentence with much / many is more common here.
Example: I need little money. = I do not need much money. Few friends visited me. = Not many friends visited me.