Revit provides IFC import and fully certified export based on the latest IAI IFC2x3 data exchange standard. When you export a Revit building information model to IFC format, the information can be used directly by other building specialists, such as structural and building services engineers.
For example, building information models developed with Revit are saved to the RVT file format. You can export the building model using the IFC format to an IFC-certified application that does not use the RVT file format. The drawing can be opened and worked on in the non-native application. Similarly, in Revit you can import an IFC file, create a RVT file, and work on the building model in Revit.
IFC uses architecturally meaningful containers to describe real-world building objects. Those containers include parameters that have meaningful values. Many standard Revit elements have corresponding IFC containers. These do not require any specific user action to export them. (For example, Revit walls export as IFCwalls.) Other Revit families (such as escalators) require that you map them to IFC containers before exporting. See Load and Modify an IFC Mapping File.