A surgical stapling system comprising: an elongated shaft assembly configured to transmit actuation motions from an actuator; and an end effector (6000, 6050) for compressing and stapling tissue, the end effector operably coupled to the elongated shaft, the end effector comprising: an elongated channel (6004, 6054); an anvil (6002, 6052) having a staple forming surface thereon, the anvil being moveable relative to the elongated channel between an open position and a closed position; and a staple cartridge (6006, 6056) removably positioned within the elongated channel, the staple cartridge comprising: a cartridge body supported for a confronting relationship with the anvil when the anvil is in the closed position; a plurality of staple drivers located within the cartridge body, wherein each one of the plurality of staple drivers supports a staple; characterised in that the anvil has a magnet located at the distal end; the end effector further comprising: a Hall effect sensor (6010, 6060) located at the distal end of the cartridge body and operable to detect the magnetic field (6016, 6066) produced by the magnet and produce a corresponding output voltage; and a microprocessor (6012, 6062) in communication with the Hall effect sensor; wherein the Hall effect sensor and microprocessor receive power when the staple cartridge is positioned within the elongated channel, and wherein the system is operable to use the output voltage from the Hall effect sensor to identify whether the staple cartridge is compatible with the end effector. an elongated shaft assembly configured to transmit actuation motions from an actuator; and an end effector (6000, 6050) for compressing and stapling tissue, the end effector operably coupled to the elongated shaft, the end effector comprising: an elongated channel (6004, 6054); an anvil (6002, 6052) having a staple forming surface thereon, the anvil being moveable relative to the elongated channel between an open position and a closed position; and a staple cartridge (6006, 6056) removably positioned within the elongated channel, the staple cartridge comprising: a cartridge body supported for a confronting relationship with the anvil when the anvil is in the closed position; a plurality of staple drivers located within the cartridge body, wherein each one of the plurality of staple drivers supports a staple; characterised in that the anvil has a magnet located at the distal end; the end effector further comprising: a Hall effect sensor (6010, 6060) located at the distal end of the cartridge body and operable to detect the magnetic field (6016, 6066) produced by the magnet and produce a corresponding output voltage; and a microprocessor (6012, 6062) in communication with the Hall effect sensor; wherein the Hall effect sensor and microprocessor receive power when the staple cartridge is positioned within the elongated channel, and wherein the system is operable to use the output voltage from the Hall effect sensor to identify whether the staple cartridge is compatible with the end effector. an elongated channel (6004, 6054); an anvil (6002, 6052) having a staple forming surface thereon, the anvil being moveable relative to the elongated channel between an open position and a closed position; and a staple cartridge (6006, 6056) removably positioned within the elongated channel, the staple cartridge comprising: a cartridge body supported for a confronting relationship with the anvil when the anvil is in the closed position; a plurality of staple drivers located within the cartridge body, wherein each one of the plurality of staple drivers supports a staple; characterised in that the anvil has a magnet located at the distal end; the end effector further comprising: a Hall effect sensor (6010, 6060) located at the distal end of the cartridge body and operable to detect the magnetic field (6016, 6066) produced by the magnet and produce a corresponding output voltage; and a microprocessor (6012, 6062) in communication with the Hall effect sensor; wherein the Hall effect sensor and microprocessor receive power when the staple cartridge is positioned within the elongated channel, and wherein the system is operable to use the output voltage from the Hall effect sensor to identify whether the staple cartridge is compatible with the end effector. a cartridge body supported for a confronting relationship with the anvil when the anvil is in the closed position; a plurality of staple drivers located within the cartridge body, wherein each one of the plurality of staple drivers supports a staple; characterised in that the anvil has a magnet located at the distal end; the end effector further comprising: a Hall effect sensor (6010, 6060) located at the distal end of the cartridge body and operable to detect the magnetic field (6016, 6066) produced by the magnet and produce a corresponding output voltage; and a microprocessor (6012, 6062) in communication with the Hall effect sensor; wherein the Hall effect sensor and microprocessor receive power when the staple cartridge is positioned within the elongated channel, and wherein the system is operable to use the output voltage from the Hall effect sensor to identify whether the staple cartridge is compatible with the end effector.