Synthesia is an AI video creation platform that allows users to produce professional videos leveraging AI avatars and voiceovers in over 130 languages. The platform's key offerings include creating videos as easily as making a slide deck, providing a wide range of AI avatars, natural voice options, 1-click translations, and numerous video templates. It caters to various use cases such as training, marketing, sales, customer service, and more, offering scalable and affordable content creation solutions.