StuffIt Engine SDK is a tool for decompressing and compressing files into and out of just about any format that exists, including SITx, SIT, ZIP, HQX, and more. By incorporating the StuffIt Engine into your software product, you can seamlessly translate files that your users may come across while using your product. For example, if you Create an email client, your client can use the StuffIt Engine for compressing and translating attachments to a format that can be sent on the Internet.