Number or Amount ?
Exemple : ‘’Could you give me an idea of the number of people who visit each month?’’
The word "number" and "amount" are often mixed up as they are used in similar situations. "Number" is used with countable nouns for example people, trees and users.
Exemple : ‘’The new wardrobe take up a huge amount of space in the room!’’
"Amount" should be used with uncountable nouns or in other words things which cannot be counted. Examples include water, space and heartache.