The words much and many mean a lot of.
- If a noun is in singular, we use much
- much money
- If a noun is in plural, we use many
- many friends
Use of much / many
In everyday English, we normally use much / many only in questions and negative clauses.
- How much money have you got?
- Carla does not have many friends.
In positive clauses with so, as or too, we also use much / many.
- Carla has so many friends.
- She has as many friends as Sue.
- Kevin has too much money.
In all other positive clauses, however, we prefer expressions like a lot of / lots of.
- Carla has a lot of / lots of friends.
- Kevin has a lot of / lots of money.
In formal texts, however, much / many are also common in positive clauses. This you will notice for example when you read English news.
Countable / Uncountable Nouns
In connection with much / many 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 many.
- 100 friends many 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 much.
- 100 money much money
Note: Of course you can count money but then you would name the currency and say that you have got 5 euro (but not 5 money).