One of the most common misconceptions about ninjas is that they always attack their enemies head-on with swords. Or that maybe they linger in the shadows and throw ninja stars.
While these happenings likely did occur, more often than not the duty of a ninja could be far more subtle.
One of the most vital tasks given to a ninja was to collect important information and communicate it to another agent or ninja.
One of the more fascinating tools of communication used by ninjas in the past was coordinated colored rice.
They would practice and study set codes that could be communicated by different patterns in rice bowls. They could summarize the information briefly by placing the colored rice in the right position on the bowl and simply set the bowl in front of the agent or fellow ninja to convey the information.
This would allow a ninja to maintain their disguise while passing on sensitive information in a public forum without risking that information falling into the wrong hands.
Most people see the kunai and think of it simply as a weapon. While they can accomplish a deadly objective, its use was far more varied by ninjas of the past.
A kunai could be used to carve holes in walls or shave boards to make it easier pass-through or slide different hidden messages.
Coded messages could also be written and attached to the handle of the kunai, which could then be thrown over a wall or outside of a compound to a waiting ninja or agent of a ninja.
At times the kunai I was also used as a step by stabbing a deeply into a wall, stepping on the kunai, and leaning over a wall to whisper or throw information.
This ninja skill utilized to convey information over large distances is very similar to Morse code.
This tactic would consist of a ninja ascending to a high location to utilize a series of movements with flags to convey coded messages to other ninjas who were within range to observe the flag movement.
The second ninja would then convey those same flag movements as there would be a third ninja who was in visual range of the second ninja, who would then also convey the information to another party.
These are just a few ways that the clever ninjas of the past would convey sensitive information to one another.
Considering how elusive and secretive ninjas could be, it would come as no surprise at all if there are even more forms of communication that ninjas utilized that we are not currently aware of.