By no means do I consider myself an expert on the subject.  However, two
points come to mind:
 
1) The reply function on most mail programs identifies the source of
"quoted" material.  The best ones name the original poster and date of the
post.  They also, by convention, mark the source material with ">."
 
2) As the net gets faster, and as users deal with more and more material,
the convention of deleting most of the quoted material saving only enough
to make the response meaningful (I'll try to do it below) smacks of the
fair use provisions.
 
This having been said, most people post/respond in a news group or on a
list server knowing they are entering into a dialogue.  It is one
thing to post and respond in the context of the newsgroup/listserve and
another to find that your material has been removed from that site and
transferred to another medium or another site.  The first is voluntary and
the second is not.
 
[As I write this, I notice that this mail server, while marking the
original post, does not carry the "from" line into the body of the
reply.  The news reader supplied by this internet provider does a better
job of identifying the original post.]
 
Bill Truesdale wrote:
 
>...we all often use the quote feature of our browsers when posting. Since
>we do not have the permission of the origional poster, are we in
>violation of copyright laws?...
>Bill Truesdell
>Bath, ME
 
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