Released in March 2006, AutoCAD 2007 was a milestone. It shifted the focus from purely 2D drafting to a more robust 3D environment, introducing:
: AutoCAD 2007 is Release 21 (internal versioning), while AutoCAD 2012 was internal Release 26.
Using a pirated serial number is copyright infringement. While Autodesk rarely sues individuals for educational use, they actively pursue companies. If you use a cracked AutoCAD 2007 to produce professional work, you risk fines starting at $150,000 per infringement.