A lot of and lots of = 'a large number or amount'. We use a lot of or lots of with both countable and uncountable nouns. There was a lot of rain last week. [rain = uncountable] There were a lot of people at the party. First thing's first: "alot" is not a word. If you want to say that someone has a vast number of things, you would say they have "a lot" of things. "A lot" is always two words.
