HSMXPress and VisualCAD are two examples of free CNC programming applications. HSMExpress is a fully featured application with CAD, CAM and CNC programming features. VisualCAD is a 2-D and 3-D design application which supports MecSoft's FreeMILL CNC module.
Other examples of free CNC programming applications include gCncCam and CAMotics. The gCncCam application is an open-source CAM processor released under the GNU general public license. CAMotics is an open-source multiplatform CAM tool that was previously released under the name OpenSCAM. The software makes it easy to simulate three-axis CNC milling and engraving, and it supports Linux, Mac OS X and Windows.