All spiders are carnivores. Their favourite menu includes insects of all kinds. Hunting spiders just probe their fangs into their prey and inject them with powerful poison. Digestive juices pumped into the prey’s body turn the insect’s insides into a soupy liquid in no time. The spider then simply sucks its victim dry because they have no teeth to chew with.
Though most people think spiders are icky, they are, in fact, very useful to man. They eat insects and agricultural pests by zillions. If they are not around, our food supplies would probably be destroyed long before they were out of the fields. Incidentally, spiders are not insects, they are arachnids and are closely related to crabs. Arachnids have eight legs while insects have only six.