A motor comprising: a stator comprising a plurality of stator cores arranged in a circumferential direction, and coils respectively wound around the stator cores; and a rotor rotatably arranged inside or outside the stator, wherein the rotor comprises a plurality of rotor cores arranged in a circumferential direction of the rotor, a plurality of magnets each disposed between neighboring ones of the rotor cores such that the magnet extends in an axial direction of the rotor outwardly of upper and lower surfaces of the neighboring rotor cores, and a molded body to support the plurality of rotor cores and the plurality of magnets, the molded body comprising a shaft hole, to which a motor shaft is coupled, wherein each of the rotor cores comprises first protrusions respectively extending in the circumferential direction of the rotor from opposite side surfaces of the rotor core contacting corresponding ones of the magnets, wherein each of the rotor cores further comprises a first end coupled to the molded body, and a second end to define a clearance, along with one end of a corresponding one of the stator cores, and wherein the second end of the rotor core comprises second protrusions respectively extending in the circumferential direction of the rotor from the opposite side surfaces of the rotor core, to prevent magnetic flux generated at the stator cores from influencing the corresponding magnets. a stator comprising a plurality of stator cores arranged in a circumferential direction, and coils respectively wound around the stator cores; and a rotor rotatably arranged inside or outside the stator, wherein the rotor comprises a plurality of rotor cores arranged in a circumferential direction of the rotor, a plurality of magnets each disposed between neighboring ones of the rotor cores such that the magnet extends in an axial direction of the rotor outwardly of upper and lower surfaces of the neighboring rotor cores, and a molded body to support the plurality of rotor cores and the plurality of magnets, the molded body comprising a shaft hole, to which a motor shaft is coupled, a plurality of rotor cores arranged in a circumferential direction of the rotor, a plurality of magnets each disposed between neighboring ones of the rotor cores such that the magnet extends in an axial direction of the rotor outwardly of upper and lower surfaces of the neighboring rotor cores, and a molded body to support the plurality of rotor cores and the plurality of magnets, the molded body comprising a shaft hole, to which a motor shaft is coupled, wherein each of the rotor cores comprises first protrusions respectively extending in the circumferential direction of the rotor from opposite side surfaces of the rotor core contacting corresponding ones of the magnets, wherein each of the rotor cores further comprises a first end coupled to the molded body, and a second end to define a clearance, along with one end of a corresponding one of the stator cores, and wherein the second end of the rotor core comprises second protrusions respectively extending in the circumferential direction of the rotor from the opposite side surfaces of the rotor core, to prevent magnetic flux generated at the stator cores from influencing the corresponding magnets.