Oracle Developer Environment Variables Introduction

Oracle Forms Developer uses many environment variables. These have default values, all of which you can modify in your own environment for different applications.
Setting Search Paths for Run Time
Forms uses some environment variables set on the middle-tier machine to search at run time for files such as forms, menus, and libraries. This enables you to build applications that are portable across platforms and directory structures by avoiding hard-coded paths in file references.
Forms searches the following paths in order until the required file is found:
The current working directory
Directories in FORMS90_PATH
Directories in ORACLE_PATH
Although you could set these variables at the machine level, such as in the Windows Registry, it is preferable to set them in the Forms environment file. Settings in this file override system settings for running a Forms application.