IT:AD:Enterprise Architect:HowTo:Understand

The following is a quick intro to EA.

Difference between Model and Diagram.
- A Diagram (think Plan, Elevation, Sections) are just perspectives of a Model (eg: 3D Model)¹⁾.
A Model can be either Physical or Logical.
- Represents a distinct and complete representation of all or part of a modeled system.
- Is the highest conceptual level
- A model is built from a hierarchy of Package/s used to represent the structure and organisation of the Model/.

A Project is a single *.eap project file, containing the Model/'s Package/s, View/s, Diagram/s, and Element/s.

The Project Browser is used to navigate the Root Node/s, and Model/'s Package/s, View/s, Diagram/s, and Element/s.

In a stand-alone *.eap Project/ file, a Root Node/ and Package/ are synonymous.

Root nodes are …

is a specialized, top level Package/, within a Model/.
By default EA Adds new Model/s as Views to Root Node/s.
Can be categorized by purpose (Use Case View, Component View, Deployment View, etc.) using different icon types.
Views can contain n nested Package/s, Diagram/s and Element/- the building blocks of your model.

When on a Root Node/ in the Project Browser/ one can use a Wizard. When doing so, EA creates a new Package/ of type x, and to help you get started, the package will contain a single Diagram/ (with the same name as the View/ Package/) and the Element/s in the View/'s default Diagram/.

A View/ – if created using an Add Model Wizard – will contain a default Diagram/ with the same name as the View/ Package/ it was added to.
Ref:
- http://www.sparxsystems.com/support/faq/diagram.html

It's reasonable to be cautious, but not unnecessarily fearful of destroying the work of others on your team:

You can't inadvertently DEL elements from the Project Browser/ and destroy many Diagram/s using the Elemen/. You have to Right-Click the element, Select Delete, and confirm that is what you want to do.
- The bad news…once it's gone, CTRL-Z will not bring it back…