Oracle A423961 - Manual (Page 124)

B – 2 Oracle7 Server Getting Started for Windows NT
Windows NT Directory Structure
Oracle Installer places all Oracle products for Windows NT into
subdirectories of
\ORANT . The actual directory names vary according to
the different products you install.
The letters nn designate the version number of the product installed. For
example, if you have installed Version 7.0 (or 7.1/7.2) of the Oracle7
Server for Windows NT, an \RDBMS70 (or 7.1/7.2) subdirectory under
\ORANT already exists. If you now install Release 7.3, the Oracle
Installer adds an \RDBMS73 subdirectory.
The subdirectories of \ORANT contain the files listed below. For all
versions of Oracle7 Server for Windows NT subsequent to 7.0, all
.DLL
and .EXE files and configuration variables have their version numbers
appended. This convention allows you to maintain multiple releases of
these items for backward compatibility. For example, the Instance
Manager executable for version 7.1 is
ORADIM71.EXE ; the executable
for Release 7.3 is ORADIM73.EXE .