Time period: 1930's, or it was argued that it started around 1918.
One of the creators is Andre Breton. There are pictures and example that are easily accessible on online.
"Surrealist techniques exploiting the mystique of accident was a kind of collective collage of words or image..."
It was based on an old parlor game where several people played. A player would write a phrase on a sheet of paper, covering part of their phrase. The next player would then finish their phrase, creating a new one. Not knowing what it was going to say was the fun part of the game. This game was also adapted into drawing. A player would fold up a piece of paper into two or three sections and create a drawing. It could be anything, or a general person/creature. The fun is to not see the other sections until the art is complete.
This game is still played, today. I remember playing it in elementary, myself. This is something to keep people entertained for hours.