SAP2000 is described as 'The SAP name has been synonymous with state-of-the-art analytical methods since its introduction over 30 years ago. SAP2000 follows in the same tradition featuring a very sophisticated, intuitive and versatile user interface powered by an unmatched analysis engine and design' and is an app. There are more than 50 alternatives to SAP2000 for Windows, Web-based, Linux and Mac. The best SAP2000 alternative is CalcSteel, which is free. Other great apps like SAP2000 are Estru3D, Robot Structural Analysis Professional, sas-civil and Abaqus Unified FEA.