File Format
Open Standard file format : ifc(2*3), dae(collada)
Commercial file format: skp(2017,Trimble), fbx(autodesk), pro(ARCHline.XP 2018_Cadline)
The ifc (2 * 3) file is the standard file format used by the Building Information Modeling industry and is available in most BIM software. For example, it can be read and edited in revit, ArchiCAD, ARCHline.XP, SketchUpPro, Rhino (using VisualARQ), etc.
https://en.wikipedia.org/wiki/Industry_Foundation_Classes
Free ifc file Viewer
BIM Vision = download-> https://bimvision.eu
BIM Vision is a freeware IFC model viewer. It allows to view the virtual models coming from CAD systems like ARCHline.XP, Revit, Archicad, Advance, DDS CAD, Tekla, Nemetschek VectorWorks, Bentley, Allplan and others without necessity of having commercial licenses of these systems or having each of particular vendor’s viewer. BIM Vision visualizes the BIM models created in IFC format 2×3. It has many built-in features and is the first viewer with plugin interface.
COLLADA (COLLAborative Design Activity) is an interchange file format for interactive 3D applications. It is managed by the nonprofit technology consortium, the Khronos Group, and has been adopted by ISO as a publicly available specification, ISO/PAS 17506.[1]
COLLADA(dae file) defines an open standard XML schema for exchanging digital assets among various graphics software applications that might otherwise store their assets in incompatible file formats. COLLADA documents that describe digital assets are XML files, usually identified with a .dae (digital asset exchange) filename extension.
https://en.wikipedia.org/wiki/COLLADA
FBX originated as a replacement file format for Canadian company Kaydara's Filmbox, a software for recording data from motion capture devices. Prior to 1996, Filmbox 1.0 used a file format called FLM. The format only supported motion data, user preferences and a list of devices used in the capturing of the motion data. This data was a serialized version of the libraries (binary dump), containing read/write memory data. This method of storing data did not work well with different versions of the Filmbox. There was also demand from early adopters of Filmbox to implement a target character in a scene with the motion capture data, to enable the visualization of the data in a 3D view with display markers.
https://en.wikipedia.org/wiki/FBX
Pro file is the ARCHline.XP's extension name. ARCHline.XP was developed by Cadline in Budapest Hungagry. (Montevideo str. 3/B., Budapest, Hungary 1037)
Visit ARCHline.XP web
skp file is the SketchUp's extension name.
SketchUp was developed by startup company @Last Software of Boulder, Colorado, co-founded in 1999 by Brad Schell and Joe Esch
SketchUp debuted in August 2000 as a general-purpose 3D content creation tool and was envisioned as a software program "that would allow design professionals to draw the way they want by emulating the feel and freedom of working with pen and paper in a simple and elegant interface, that would be fun to use and easy to learn and that would be used by designers to play with their designs in a way that is not possible with traditional design software. It also has user friendly buttons to make it easier to use."
https://en.wikipedia.org/wiki/SketchUp