SITX - StuffIt X Archive is a format that is highly useful and can be used for compression of different files. The good thing about this format is that it offers up to 20% more in compression for your saved files on your computer. There are also long file names that can be supported by this format as well, and that is the main reason why people take advantage of it while they can. Previously, it had been developed by a different company. There are different reasons why people use this encryption format, and one is to give off great security when you are compressing your files.