license <-> copyright

[Toon Knapen]

I'm new to this ml, so maybe the question
is alreay answered (but I found no archive)

So, can someone point me to a website or explain
the relation between a sofware license and 
a copyright.
As I understand it, the copyright holder can
define the a license on his work which stipulates
what you can do with his work without breaking
the copyright.

Next I also wanted to ask if a copyright is
transferable. For instance : is it best that
all developers in an open-source project transfer
their copyright to the project manager ?

Finally I also wanted to ask why a copyright
notice always includes dates (years). Do these
indicate the year the 'work' was released to
the public ?

Thanks,

toon

-- 
Toon Knapen				toon at si-lab.com
Si-Lab
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