The Duplicate Layer command adds a new layer to the image which is a nearly identical copy of the active layer. The name of the new layer is the same as the name of the original layer, but with ΓÇ£ copyΓÇ¥ appended to it.

If you duplicate a background layer which does not have an alpha channel, the new layer is provided with one. In addition, if there are any ΓÇ£parasitesΓÇ¥ attached to the active layer, they are not duplicated. (If your understanding of the word ΓÇ£parasitesΓÇ¥ is limited to small, unpleasant creatures, please ignore the last sentence.)