NXPowerLite will compress PDF, JPEG, Microsoft PowerPoint and Word files simply and effectively, making them easy to email as attachments. It is especially effective on files that don't zip well. Optimized files stay in the same format - a PDF remains a PDF. It will look and feel identical to the original, just much smaller. You can optimize and automatically attach files to a new email by selecting the files and using 'Optimize and email' in Finder. One key for Mac or Window-Registration keys for NXPowerLite Desktop will work with either the Mac or the Windows version, so if you switch platforms you can keep using NXPowerLite. It also means if you are buying multi-user licences you don't need to specify how many of each platform you want up front.