The spiders forms a web of non sticky threads in which the flies gets stuck. Some spiders lie in wait for their prey at the center of the web. Some spiders bites the prey, which is full of venom.
A spider web is a net which spiders make to catch their prey. These webs can be tangled webs or cobwebs which are made in the corners of the rooms. All spiders do not make webs, some directly catches the prey.
Different spiders catch the prey in different ways, some spiders make the web with non sticky threads, to catch the prey in the center of the net, and some spiders like jumping and wolf spiders directly catches the prey and bite them.
Thus, some spiders catches the prey by making spider web and some directly catches the prey by biting them.
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