What makes a language... a language?

Outside of China, Mandarin and Cantonese are often referred to as Chinese dialects, despite being even more dissimilar than Spanish and Italian. On the other hand, speakers of Danish, Norwegian, and Swedish, which are three distinct languages, can usually communicate with each other in their native tongues. So, when is speech considered a dialect versus a language? Martin Hilpert investigates. [Directed by Luísa M H Copetti, Hype CG, narrated by Addison Anderson, music by Gabriel Maia].