I know what is a polygon but when a polygon is said to be double digitized? I failed to find a suitable meaning of double digitized after googling. I understand double digitized means digitized twice, so I hope it would be enough if someone explains what does digitized polygon mean. I found the term double digitized from source . ESRI Shapefile Technical Description (page 1)
When I googled for "double digitized" the fourth non-paid result was the Practical Handbook of Digital Mapping Terms and Concepts by Sandra Arlinghaus:
when polygons are recorded as closed loops of coordinates, the first and last coordinates are the same; therefore, boundaries of adjacent polygons are digitized twice.
I would also call it double-digitizing any time the same polygon is inadvertently digitized a second time.