DeepSky Stacker is a very popular and capable stacking program widely used by astrophotographers around the world. Best of all it is freeware and available in 12 languages thanks to the generosity of its author. DeepSkyStacker is actually very simple to use but can be daunting at first if you are not familiar with the terms and phraseology used by stacking programs. The many options available with the program can also confuse new users as often which option to use and which one to ignore is not that apparent. However, once the terms and phraseology used with stacking are understood, the program becomes quite simple to use.