One of the principles of Jewish faith is belief in the resurrection of the dead. According to the Zohar—an early Kabbalistic text—the resurrection will take place forty years after the arrival of Moshiach. However, certain righteous individuals will arise with the coming of Moshiach. All the dead will be resurrected in the Land of Israel.
There is a small bone in the body called the luz bone (some identify this bone as the coccyx), from which the body will be rebuilt at the time of resurrection. Our daily prayers are replete with requests for the resurrection, and there are many customs connected with it. (See the book To Live and Live Again by the present author, published by S.I.E. Publications.).