An Instance represents a software technology running in one or more Environments, that supports builds and/or deployments.

...

• You may have an Oracle SOA Suite Instance (SOA1) for most composites, and a second Instance (SOA2) for hosting composites which contain sensitive information such as financial or HR related data.In this case, you would create two Instances in FlexDeploy named SOA1 and SOA2. You can define Name and Code for Instances as per what makes sense for your topology.
• You may have a requirement to perform builds using multiple versions of JDeveloper, such as JDeveloper 11.1.1.9 and JDeveloper 12.2.1. In which case you can create JDEV11119 and JDEV1221 Instances. Then you can associate each Instance with one or more Environments, and describe which endpoints fit in each Environment Instance combination.

Example #1 Instances for ADF Build/Deploy

...

By default, all active Instances are displayed in the search results. To refine the search results, type all or part of the instance name into the Search box, and the list will automatically filter. Uncheck the Active checkbox to show the inactive integration instances as well.

Creating or Editing Instances

...