There are so many languages in the world. Increasingly more of the world knows English but not always. If you are travelling deeper into India for instance, the dialect changes every few hundred kilometers and the language itself may change within 300 to 400 kilometers. In Bangalore people speak Kannada, the native language in addition to English, Hindi, Telugu or Malayalam. Travel 400 kilometers any direction and sure enough you will find speakers speak Tamil or Malyalam both very different from Kannada.
Alex Gendler explains this evolution of language. He maps the origin of how languages may have started and how with migration, geographic changes and eating habits different tongues evolved.
In this educative video from TED-Ed explore how languages grew and understand how linguists or language experts are trying to find if all languages might have had a root language.