The Island is the geographic location featured in Lost and web series Missing Pieces.
The Island has healing powers and cured John Locke of his paralysis and Rose of her cancer. It also functions as a "cork" that suppresses a dangerous force from escaping. At the Heart of the Island is a bright light, the source of "life, death, (and) rebirth" that needs to be protected. The current protector is Hugo Reyes. The protector also brings others to the island for various purposes, such as becoming the the new protector of the island.
The Island was inhabited by Egyptians and possibly Sumerians and Southeast Asians in the distant past, and also was home to a village of Latin-speaking people who were shipwrecked there in the early first millennium. The Island periodically moves its physical location. The Island was in the South Pacific Ocean in 2004 and appears to have been in the Mediterranean Sea at some point in its history. Its current location is unknown.
According to Jacob, the Island acts as a cork, holding back a malevolent force that would destroy the world if released. When the Man in Black made contact with the site of this suppression, the Heart of the Island, he transformed into a smoke monster that plagued the Island for thousands of years. A protector guards the Heart of the Island, the source of life, death and rebirth. Despite the Heart, or possibly because of it, not all who die on the Island move on - some remain, whispering. Other apparitions of unknown origin also appear, often confronting people with images from their past.
The Heart of the Island manifests itself as electromagnetism concentrated in specific pockets. The Man in Black's people dug wells at these sites, and the Dharma Initiative built stations, including the Orchid and the Swan. Since at least 1977, when scientists penetrated a pocket, this energy has healed sickness, including cancer, paralysis, brain damage and male infertility, but it causes pregnant women to reject embryos, killing both mother and fetus. The electromagnetism also affects navigation, hiding the Island from the outside world, drawing back those who leave the Island, moving the Island and even transporting travelers through time.