What is a .pyd file

[David Humphrey]

I understand .py, .pyw, .pyc and .dll files.  However, I see .pyd files in
the ActiveState Python 2.0.203 tree, e.g., multiarray.pyd in the Numeric
directory; also much of the win32 extensions.  multiarray.pyd looks like a
Windows DLL and dumpbin seems to agree.  Is it built as a DLL and then
renamed?  If so, why?

Regards,
David L Humphrey
Manager, Software Development
Bell Geospace, Inc