A robot is defined as a reprogrammable, multifunctional manipulator designed to move materials and tools to perform tasks. Robots are classified as pick and place, continuous path control, or sensory based on their motion and use of feedback sensors. Pick and place robots move items between points without a specific path, while continuous path control robots follow a programmed path for tasks like welding. Sensory robots use sensors for closed-loop feedback and higher accuracy in applications such as mobile robots.