People from different language groups and cultures need to communicate with each other and must find communication tools. On one level, they can rely on specially trained professionals who can proficiently use two or more languages for interpretation and translation. But this is inconvenient, and the time and cost are expensive. Therefore, throughout history, there has been a common language. In the ancient world and the medieval world, it was Latin, in the West for centuries it was French, and in Africa. Swahili was spoken in many areas, and English was spoken in most parts of the world in the second half of the 20th century.
 The universal language is an effective means of dealing with language differences is meant to illustrate.