Any product package that you install using IBM® Installation Manager comes with a version of the Eclipse IDE or workbench; this included workbench is the base platform for providing the functionality in the Installation Manager package. However, if you have an existing Eclipse IDE on your workstation, then you can extend the IDE by adding the additional functions provided in the product package or packages that you are installing.
To extend an existing Eclipse IDE: On the Location page of the Install Packages wizard, select Extend an existing Eclipse IDE.
You might extend your existing Eclipse IDE, for example, to gain the functions that the product package provides, but you also plan to retain the preferences and settings in your current IDE when you work with the function from the product package. You also might plan to work with plug-ins that you have installed that already extend the Eclipse IDE.