The Shroud, if you are new to the western world, is a cloth imprinted with the face and body of a bearded man; that would be Jesus Christ, according to the theological believers, because the Bible says he was wrapped in cloth and place in the sepulcher. That this imprinting happened at all is one of those random mysteries that make the natural world so appealing.
It's now kept in a sealed case in Turin, but various analyses have been done over time and they showed the cloth was not old enough to have been used to cover Jesus.
Yet a new book says those other tests, like carbon-14 dating, were inaccurate. Believers said the tests purporting it to be from the 13th century or so were contaminated with fibers from that period. The Catholic Church has never said it was real, they instead have said that since it recalls the Passion of Christ, it is a 'mirror of the Gospel' and therefore is an object for meditation, but plenty of people want to believe it is real. The new tests used infra-red light and spectroscopy on the same fibers from the 1989 study debunking its early Christian origin. They concluded the cloth was from the period around the time of Jesus, but they're not able to narrow it down beyond a few centuries.
Turin Shroud 'is not a medieval forgery' by Nick Squires, Telegraph
Shroud of Turin. Credit and link: Telegraph