The purpose of the Pentaho Design Studio is to facilitate the creation and management of files within your Pentaho solutions. The Design Studio helps organize these files and provides editors for each type of file. There are several levels of organization within the Design Studio: workspaces, project, views, editors, and perspectives. If you haven't done so already start up the design studio and take a look at the basic layout.
A workspace is the directory that contains a collection of projects, along with preferences and other settings related to the projects it contains. The Design Studio comes with a workspace already set up - feel free to change it or its location if you like. After the workspace location is chosen, a single Design Studio window is displayed. A Design Studio window offers one or more perspectives. A perspective contains editors and views, such as the Navigator. Multiple Design Studio windows can be opened simultaneously. A workspace allows you to organize groups related of projects. You may find it helpful to have all reporting and BI related projects organized into a BI specific workspace.