Without the presence of any kind of media they made the Quit India movement go viral way back in 1942. Within days the whole nation was aware of the movement. There was a huge army of volunteers who would paint the messages on the walls in the dark of the night, even in the most distant villages of the country. The concept of posting messages on walls could have started from there, the same message being posted on different walls in different languages, to create a wave which would jolt the whole nation awake.