What is a WebLogic Server domain?

A domain is the basic administrative unit of WebLogic Server. It consists of one or more WebLogic Server instances, and logically related resources and services that are managed, collectively, as one unit.

A domain includes one WebLogic Server instance that is configured as an administration server. All changes to configuration and deployment of applications are done through the administration server.

The administration server provides a central point for managing the domain and providing access to the WebLogic Server administration tools. These tools include the following:

• WebLogic Server Administration Console: Graphical user interface to the administration server.
• WebLogic Server Node Manager: A Java program that enables you to start and stop server instances—both administration servers and managed servers—remotely, and to monitor and automatically restart them after an unexpected failure.
• Note that the node manager is installed on all the machines that host any server instance – both administration server and managed servers.

Here are some of the screenshots:

 

https://www.quora.com/What-are-weblogic-servers-and-what-are-they-used-for