Most secrete powerful digestive enzymes which are injected into the prey to liquify it. Once dissolved in its own epidermis, the prey is sipped like a root beer float. Scorpions date back to the Silurian, about 425 mya, and may be the first terrestrial arthropods. Not all spiders spin webs. Wolf spiders are the tigers of the leaf litter, and the common jumping spider leaps several times its body length to catch its prey.
Spiders use pedipalps as copulatory organs.
Most are very tiny, less than 1 mm long. The cephalothorax and head are fused into a single unit. It has an oval body with extremely long legs, which they frequently lose in various accidents and brushes with predators. They are predators, herbivores, and scavengers. Look at them closely next time you see one.