Researchers in Sweden have unlocked one of nature's biggest secrets. They worked out how spiders make such strong silk for their spider webs. The spider's silk is very strong. It is tougher than steel. For decades, scientists looked into what makes spider silk so amazing. Finally, researchers in Sweden have found the answer. They found that a spider's silk gland has a special acid level. This helps to make the silk very strong. The researchers copied this process and made enough artificial spider-web silk to stretch for one kilometer.

The new artificial silk could be very useful. Doctors are interested in it for stitches. They also think it can help the skin after a burn and replace torn ligaments in the body. Airplane companies and makers of protective clothes also see many uses for the new silk. A researcher spoke about how important the discovery could be. She said: "This is the first successful example of [copying] spider silk spinning….This may allow industrial production of artificial silk for bio-material applications or…advanced textiles." The silk could be an important new material for us in the future.