10 Things You Didn't Know About Ninjas

International Ninja Day is December 5th, here are ten facts about the mysterious warriors.
1. Ninjas were known for their skills in guerrilla warfare, assassination, sabotage, espionage and infiltration.
2. Though secretive, ninjas adhered to a strict hierarchy that eventually evolved into larger territorial guilds.
3. Ninjas were heroes to the lower classes in Japan, often recruited by those unable to afford the services of the upper-class samurai.
4. Because they didn't carry large swords, Ninjas often used whatever was available as a weapon.
5. Employing secrecy as a means of survival, ninjas also encouraged exaggerated tales of their exploits to incite intimidation.
6. Ninjas wearing all black is a modern day conception. They did their best to blend in to their surroundings.
7. Part of ninja training included in-depth knowledge of various forms of medicines, including a mysterious "black medicine" used to stop bleeding.
8. Ninjas used little "smoke bombs" of ash contained in an eggshell to create confusion or misdirect their enemies.
9. Female ninjas were common. They often used hair pins and nail attachments as weapons.
10. Ninjas would often carry crickets, using their chirps to cover the sounds of their movements.