A 'solution' refers to your project data, results of workflow operations, flow simulation cases, and other information that you imported or created in the application. It is called 'solution' (not 'file') as all the data contained in a solution can be saved to file (*.jewel) as well as to a centralized database called Data Management System (DMS). Solutions saved to DMS can be managed with the dedicated DMS button-group of the strip.