How do speaker stands function?

[Snax]

Are speaker stands used to lift the speaker higher and closer too your ear or do they provide a medium for some sort of sound dampening?

I ask because I am trying to work out how to place my speakers (bookshelf speakers). They can sit on a marble floor, a wooden table or I could buy some stands.

Is the marble floor terribly bad?

 

[Snax]

so blue tac on a marble floor is fairly solid? or would it still vibrate?

 

[Snax]

I have been reading around. Am i correct in thinking that solid marble floors would allow me to place bookshelfs onto them with blu tac on the corners? The floors wont vibrate and the blu tac will help the speaker from vibrating against the floor?

 

[Snax]

Thanks very much. That was a very useful reply. I shall have fun playing with them later on tonight.