Silk comes from the cocoons of certain insects, such as the mulberry silkworm. When the insects create their cocoons, harvesters extract the fibers and spin them into thread. Each cocoon may contain more than 1,000 yards of fibers, but it takes several to create thread strong enough to make cloth.
The vast majority of the silk produced in the world comes from China, as of 2014. India, Uzbekistan, Iran and Brazil are also major producers of the cloth.
Spiders also produce an extremely strong silk fiber, but the amount produced is much less than what goes into a silkworm cocoon. Attempts have been made to create silk artificially in the laboratory by grafting silk-producing genes onto other animals and even plants to relieve stress on silkworm populations and reduce production costs.