Fusion 360
In short: Fusion 360 is a cloud CAD software by Autodesk for 3D design, simulation and manufacturing.
In more detail: It combines parametric modelling, assemblies, rendering and CAM in one program.
In Depth
Use
For hobby and start-up projects there are limited free licences, for companies it is paid. Typical flow: sketch, extrusion, part, export as STL for 3D printing.
See also: CAD, TinkerCAD, 3D Printers, Blender