I’ve been involved with computers since 1978, so I’ve seen the evolution of operating systems and user interfaces.  It occurred to me today that there are three “phases” that have happened (or are happening).  I have some transportation analogies for this:

Unicycle ( unix, dos, cp/m ) – like a unicycle, these operating systems could pivot on a dime, they were small, and cool.  They weren’t very easy to use though, and took considerable skill on the part of the rider (operator).

Car ( Windows XP, Mac ) – like a car, these operating systems were much easier to use than the Unicycle.  They were fast and useful.  While they couldn’t quite pivot like a Unicycle, they were still very flexible.

Train ( Windows 8 ) – Even easier to use than the car, but it only goes forward and backward on the track.  The attempt to dumb down the user interface so it can be supported on all devices and screen sizes necessarily limits flexibility.