The concept of the Ninja Turtles originated from a comical doodle drawn by Kevin Eastman who was brainstorming with his buddy named Peter Laird that night. Unlike many comic book superheroes and characters, the Ninja Turles (also known as the Teenage Mutant Ninja Turtles) did not begin with a popular comics company like Marvel or DC.
Just the thought of turtles that move like ninjas is already quite appealing! This is probably the reason why Kevin Eastman and Peter Laird's idea of the Ninja Turtles has made it big. If the shell is gone, the turtle is good as gone too.
Many people see turtles as really slow and weak creatures that are vulnerable to predators without any defense aside from their sturdy shell.
