The end of arm tool is the hand that goes on the end of your robot arm. Historically, these are custom designed according to the application to ensure that the robot can reliably pick up the product. Off the shelf components such as pneumatic grippers, suction cups, tool changers, crash protection, and force/torque sensors are commonly used together to form a complete solution.
More recently, there has been a trend toward gripper flexibility, so that tool changes are not as necessary. This increases up time and throughput. Adaptive servo grippers such as the Robotiq 2-finger gripper are a good example of this new technology.