Quantifiers form a sub-class under determiners. They are adjectives or phrases that serve to answer two possible questions: 

1.    How many?

2.    and How much? 

For example: a few, a little, much, many, most, some, any, enough, etc., are quantifiers.

Quantifiers that describe quantity

Words and phrases that describe quantity include a little, none, a few, etc. Some of these are used only with:

 Countable nouns - These are the nouns  that answer the question How many? For example: a few, a number of, several, etc.

Uncountable nouns - These are the nouns that answer the question How much? For example:   a little, a bit of, etc.)

Some of them are also used with both. These are the ones that answer both questions. For example: such as no/none, some, a lot of, etc.