Workspaces are like separate screens or desktops. You can only display one workspace at a time, but applications in all workspaces can run simultaneously. To display another workspace, you click its button in the workspace switch in the center of the Front Panel.
By default, four workspaces named One through Four are available.
You can specify whether an application is displayed on one or all workspaces by clicking mouse button 3 on its window frame and selecting an item from the pop-up menu.