Goose versus duck

A goose has a longer neck than a duck. The males and females have the same coloration and markings; male and female ducks of the same species are different. Geese are grazers on land,mostly, and ducks almost exclusives feed in the water. Roger Lederer. For more information on wild birds, see www.ornithology.com
On line I have been seeing photos of geese called ducks. Since I grew up on a farm I know at a glance if its a goose or a duck.
I looked on line to see what they said and this was what I found, this is not right because white pekin ducks the male and female are the same color but most male duck and female ducks of the same kind are different colored.
The goose is larger and has a longer neck, more the size of a turkey. A duck has shorter neck and legs but both the goose and ducks love water
I would like to have some ducks but I don't because you need a pond for them just like the geese.