Venomous snakes produce toxins in specialized glands and deliver them through fangs or other specialized teeth to subdue their prey or defend themselves. On the other hand, non-venomous snakes do not possess these specialized glands or delivery mechanisms for toxins. Additionally, venomous snakes often have distinct triangular-shaped heads and vertical pupils, while non-venomous snakes usually have rounded heads and round pupils. It's important to keep in mind that not all snakes are harmful, and many non-venomous snake species are harmless to humans.