PostgreSQL & Object Oriented

Hi,
"PostgreSQL is a sophisticated Object-Relational DBMS, supporting almost
all SQL constructs, including subselects, transactions, and user-defined
types and functions. It is the most advanced open-source database
available anywhere. Commercial Support is also available."

is written on main page...

Object Oriented Database -> ok
RDBMS -> ok

but what is Object-Relational ? Could someone explain it please?

Regards ang best wishes,

Devrim GÜNDÜZ

devrim(at)oper(dot)metu(dot)edu(dot)tr
devrim(dot)gunduz(at)linux(dot)org(dot)tr
devrimg(at)tr(dot)net

Phone : +90-535-328-9594 (cellular)-
Phone : +90-312-295-9595 (work)
Phone : +90-312-286-5906 (home)

Web : http://devrim.oper.metu.edu.tr
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