According to Runway,  they developed " a new AI Magic Tool that allows you to transform your images simply by using a natural language description." 

But according to ArsTechnica, " Video generation promises aside, what seems most novel about Runway's  Text to Video announcement is the text-based command interface. Whether  video editors will want to work with natural language prompts in the  future remains to be seen, but the demonstration shows that people in  the video production industry are actively working toward a future in  which synthesizing or editing video is as easy as writing a command."

More here on ArsTechnica

Photo by Pierre Bamin