Nobody has noticed until now, but sometime in the first months of 2013, the Linux desktop slipped into a new era. So far, though, the characteristics of that era have been haphazardly defined—when they have been defined at all.
Broadly speaking, the history of the Linux desktop can be divided into four main eras. The first might be called the Pre-Desktop era, in which many the command line was the interface of choice, and such graphical interfaces as were in use were window managers, which were limited in both usability and utilities. Symbolically, at least, it ended with the release of KDE 1.0 in July 1998.
Next came the GNOME-KDE era, in which these two desktops were so widely used on Linux that many users had barely heard of alternatives. During this era, both KDE and GNOME improved rapidly, overtaking Windows and OS X in features, although not always in polish or consistency.
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