There is only one file type that uses the .LCF extension:
ArchiCAD Library Container File
Stores a complete hierarchy of libraries used by ArchiCAD, an architectural design program; may include individual objects, folder structures, .PLA files, and other LCF files.
All libraries and library objects that are loaded with an ArchiCAD project can be saved into a single LCF file using the ArchiCAD Library Manager. Library Container Files load two to three times faster than individual libraries.
Updated: June 1, 2009