I would refer you to the anthology "Storming the Reality Studio: A Casebook of Cyberpunk and Postmodern Science Fiction"
http://www.amazon.com/exec/obidos/tg/detail/-/0822311585/002-2854538-8920824?v=glanceThe "cyber" part of the term is fairly easy to understand. I think most people are confused about the "punk" part. I would argue that the 'punk'-ness comes from the attitude toward authority and popular culture most genuinely cyberpunk works take.
Another link common to the cyberpunk genre is its reliance on and reinvention (or reimagining?) of the themes/archetypes/tropes of
film noir.
Is cyberpunk alive or is cyberpunk dead? That, to me, is a more interesting question in our post-
Matrix world. For me,
The Matrix is to cyberpunk what Green Day is to punk music.
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I would agree, however, that the term 'cyberpunk' is often mis-applied to just about any book or film that has technology as its central concern.
However, some critics argue that
Frankenstein was the first cyperpunk novel. :shrug:
I once read an interesting literary journal article about the connection between cyperpunk and gothic literature--more specifically,
Neuromancer as the classic "haunted castle" tale.