Navisworks Manage and Navisworks are two different products. Navisworks Manage is a Plant Design Management System (PDMS) used in the engineering, construction, and operations industries for 3D design, production, and coordination. It enables users to open, view, and combine multiple file formats, including dwg, dgn, IFC, and Revit, into a single model.
Navisworks, on the other hand, is a 3D design review software used to open and view files created in various design and modeling applications, such as AutoCAD, Revit, and Navisworks Manage. Navisworks can also be used to create animations and simulations, and to perform clash detection.