Hello micheus,
I think AMF's biggest feature over STL is having different parts of the object the slicer can know are made from different materials/filaments, for 3D printers that can print from more than one filament at a time. From what I've read it is doable with STL but each part has to be exported to separate STL files for each kind of material and then re-entered together again at the slicer software. AMF also has complex color features like gradients and bitmaps can be mapped to the faces but printers with those capabilities aren't as common. It could be it might be used in other applications like CNC but I wouldn't be sure
I think AMF's biggest feature over STL is having different parts of the object the slicer can know are made from different materials/filaments, for 3D printers that can print from more than one filament at a time. From what I've read it is doable with STL but each part has to be exported to separate STL files for each kind of material and then re-entered together again at the slicer software. AMF also has complex color features like gradients and bitmaps can be mapped to the faces but printers with those capabilities aren't as common. It could be it might be used in other applications like CNC but I wouldn't be sure