[Tagging] What exactly is a greenfield?

[Dave F.]

  On 05/10/2010 12:15, Richard Mann wrote:
> A greenfield site is one that is currently a field, so it should be
> tagged as a field until it gets built on. Nothing should ever be
> tagged "greenfield".
>
> A brownfield site is derelict land that was something once, but is now
> nothing in particular until someone does something with it. A
> "brownfield" tag would therefore make some sense, though I'd probably
> leave it as landuse=industrial (or whatever else it was) and add
> further tags to say that it's derelict.

Not sure this is correct. Both are a description of land that has 
planning agreement with the local authority for future development.

Dave F.