The meaning is exactly the same. The only difference is that 'lots' sounds more informal, and possibly more enthusiastic.

Hello Danyel 'many' and 'lots' mean the same thing. 'many' is more formal - in writing and 'lots' when we're talking. Don't you just love English!? :) Maybe someone else has a better idea?

Lots of is normally used in affirmative sentences. It can be used with countable and uncountable nouns. Many is normally used in negative sentences or questions. There aren't many museums in London. so, It is better you use lots of instead of many.