artcam.com goes to the main artcam page. Under products, it lists the free, standard and premium. I searched all over the website last night trying to find out if there were any conditions to the free license (could I use it commercially, for example) and never found that kind of information. The best I could see is that the free is designed for beginners and hobbyists. I did find a matrix comparing the features of the various versions, but, of course, I can't find that today.