Spiders are helpful to people because they eat harmful insects. They eat grasshopper and locusts which destroy crops. Spiders also eat flies and mosquitoes which carry diseases. Spiders feed mostly on insects but some capture and eat tadpoles, small frogs, small fish and mice. Most females are larger and stronger than the males and occasionally they eat males.
Spiders can live anywhere they can find food like fields, woods, swamps, caves and deserts.
One kind of spider spends most of its life underwater. Another kind lives near the top of Mount Everest, the world's highest mountain. Some live in houses, barns, and other buildings. Others live on the outside of buildings, on walls, windscreens and cornersof doors and windows. The life span of arachnids in temperate areas is a single season, therefore they rely on eggs to perpetuate the species from year to year.