[Proj] cs2cs for datum conversion and the "towgs84" parameter

[Hamish]

Gerald I. Evenden wrote:

> I feel that confusion of the above is related to persistant lack of 
> documentation/education that will separate the concepts of projections
> and datum shifts.  But, alas, I am beating an old drum.  Sorry.


Hi,

I have attempted to gather some relevant information at the link below;
expansion of the wiki page with further documentation (links,
paragraphs) suited for new users is warmly encouraged, as is linking to
the page if you find it useful or need to refer someone to a quick cite.
It needn't be GRASS specific and will probably end up being better
written if it isn't.

http://grass.gdf-hannover.de/wiki/Gis_Concepts#Background_material


> education that will separate the concepts of projections and datum
> shifts.

Such a paragraph written by an expert hand could be a quite useful
addition.


regards,
Hamish