Spiders can be feared or hated, but they represent one of the manifestations of the life of the animal world, and people have to put up with their existence. Spiders live everywhere, in almost any natural environment that can support living organisms. These creatures dare to live in an aquatic environment, and some species are even able to tolerate the effects of salty sea water. There are huge interspecies differences among spiders, both in color and size. Arachnids are also one of the most numerous classes among invertebrates and provide many opportunities for amateur naturalists to observe and study. This work will undoubtedly appeal to amateur naturalists. It highlights such thrillingly interesting topics as the structure and growth of spiders; producing cobweb silk and weaving fishing nets; jaw claws and venom; spider camouflage, their hunting nets, tunnels and funnels; courtship and breeding processes; self-defense.