Yes some of them do make a silken ground-cover for the spot that they like to stand on while waiting for prey. They stand at the center of the (usually raised) spot where they like to stand and turn around and around while expelling silk in a broad band from their spinnerets. Then they keep extending the edges until they have enough covered to satisfy themselves.
Tarantulas that live in burrows will cover the walls of the burrow with webbing to improve their footing and to help prevent cave-ins. The method is the same.
Tarantulas that live in trees and bushes will make vertical silken "socks" to live in. The method is the same, but they start at the top and apply silk in a vertically hanging circle around themselves until they get the "sock" long enough to satisfy themselves.
Spiders keep their webs as long as they are alive.
When ever they want to . But some do not make webs
Spiders make unique webs because they do not want other spiders coming into their webs. They have a unique shape, design, and scent to keep other away.
yes.
NO
trapdoor spiders
orb spiders
spiders make webs
yes they do
no, but SPIDERS spin WEBS.
If by "redback spiders" you mean the kind of widow spiders that grow in Australia, they make the same kind of three-dimensional tangled filament webs that all the member of their Family make. Some other kinds of spiders make orb webs, sheet webs, etc.
Yes