Xforce Keygen is a type of software crack or key generator that is sometimes used to activate or license Autodesk software products. However, I must stress that using such tools is not recommended and may be against the terms of service of Autodesk's software.
Autodesk 2015 refers to the 2015 versions of Autodesk's software products, such as AutoCAD, Revit, Maya, 3ds Max, and more. These software products are widely used in various industries for tasks such as drafting, modeling, simulation, and rendering.
That being said, here is some general information: