There are hundreds of species of spiders, most of them very small. They all have eight legs and a two-part body. Most are shy and totally harmless to humans. They are far more beneficial than pesky.
Spiders are by far the most important predators, killing more insects than all other predators combined. They feed on a broad variety of pest insects year round.
For shelter for spiders, cover bare dirt in your garden with a mulch of dead leaves or grass clippings that is thick enough to shade the soil surface.