Microsoft is characterizing Skype Translator as "a brand new feature from Skype." The new service translates conversations both ways in near real-time. The service will display an on-screen transcript of the call, and also ultimately will translate instant-message chats in more than 45 languages.
Initially, the preview available on December 15 is available on devices running Windows 8.1 or Windows 10 Technical Preview, though Microsoft is expected to make it ultimately available across a wide variety of devices and operating systems over time. Today's preview also is currently available in only in English and Spanish.