What is the difference between a "project" and a "design"?

"New Project": Select PCB project and PSpice project.
"New Design": Create only PCB project.
(In PCB project,
- Online DRC checks schematic and layout netlist design status
- Simulation is not possible in versions below 17.2)

Simulation is also available for PCB project in versions 17.4 and higher.

"New Project": Select PCB project and PSpice project.
"New Design": Create only PCB project.
(In PCB project,
- Online DRC checks schematic and layout netlist design status
- Simulation is not possible in versions below 17.2)

Simulation is also available for PCB project in versions 17.4 and higher.

Thanks, but I'm still confused. I am using PSPICE for TI 17.4. As you say, when I create a "New Design", I can run a (PSpice) simulation on it. In what sense is this then *not* a PSpice project?

My first assumption was that I could create different "designs" within a project to experiment with different versions / design solutions applicable to the same project / problem / assignment.

Is there even a hierarchical relationship between "projects" and "designs"? Can "designs" belong to a "project"?

A project file (.OPJ) is a container for the design file (.DSN). There can be only one design file in a project. The project file stores pointers for interacting with the design file, other referenced files, and outputs reports associated with the design file.

When the project is first created, the project manager creates a design file with the same name as the project.

If you create a new design file, or move or copy a different one into the project, the project manager will ask you if you want to replace the existing
design file.

You can view the hierarchy using the File tab in the project manager.

Thanks, that helps a lot!

What does the Design file specifically contains? Model lib...schematic...nested schematic..Design cache,,,simulation profile? An engineering project is supposed to have many designs. First time hearing that a project can have only one design.

A single DSN file is included in the project file. The "design cache" is included in the DSN or OLB, and other files are included in the project file as separate files or linked .