[plt-scheme] The role of proper and improper lists?

> Perhaps you would use use them to represent trees (?), but beyond that
> I am not familiar with other uses. Improper lists are an option
> because we are provided with 'cons; there is nothing more to it than
> that.

<tree> -> ()
<tree> -> (<element> <tree>*)

The above, to me, seems an intuitive definition of what a tree is.
Using an improper list to represent a tree does not seem intuitive to
me and, therefore, it is unlikely I would use them to represent trees.

Cheers,

Marco