Lots of and A lots are the same thing with countable and uncountable nouns, singular and plural. But much or many is more formal, and they express a lot and quantity.
Lots of and a lots
We use "a lot of" and "lot of" with both countable and uncountable nouns. And also with the singular and plural, examples:
Singular:
- A lot of water is wasted.
- Lots of water is wasted.
in plural:
- A lot of computers are needed at schools.
- Lots of computers are needed at schools.
Much and many vs. a lot of
The use of "a lot of, much, and many" have the same meaning, but we often use them differently.
For example, we use "a lot of "mostly in affirmative sentences, but in negative and questions we prefer "much and many". Examples:
- He watches a lot of films. (positive)
- He doesn’t watch many films. (negative)
- Do you watch many films? (Question)
- He drinks lots of coffee. (positive)
- He doesn't drink much coffee. (negative)
- Do you drink much coffee? (Question)
We sometimes use "a lot of" and "lots of" with negative sentences instead of "much" and "many". We use it in a question when we think the answer will be "Yes":
- I don't like a lot of salt in my food. = I don't like much salt in my food.
- Do you get a lot of snow here? = Do you get much snow here?
- Were there a lot of people at the football match? = Were there many people at the football match?