[ Thanks to James Maguire for this link. ]
“Virtual desktops go by a variety of names. Unity and the GNOME
2 series of releases call them workspaces, while GNOME 3 calls them
activities. KDE offers activities, each of which can be divided
into separate virtual desktops. However, all the names refer to the
same basic concept: additional spaces that you can use to reduce
the clutter on your screen and organize your open windows.”