.XSF File Extension

File used by InfoPath, a program used for creating forms; specifies the content, properties, and structure of the form template (.XSN file); stored as one of the files inside of the XSN template; adheres to the InfoPath XSF schema (an .XSD file) published by Microsoft.

Three-dimensional model file created using Cal3D, an open source character animation program; contains parent to child relationships between the characters skeletal bones (torso, legs, arms, etc); used for creating character motion.