Revelation 1:4

Asia : A Roman province on the west side of Asia Minor.
(39° 13´, 32° 43´)

John : a son of Zebedee; younger brother of James; the beloved disciple of Christ,a relative of Annas the high priest,a son of Mary the sister of Barnabas, and surnamed Mark,the father of Simon Peter

Revelation 1:8

Alpha : a title of Jesus Christ

Omega : the last letter of Greek alphabet

Revelation 1:17-18

Alpha : a title of Jesus Christ

Hades : the place of departed spirits (NIV notes); the unseen world (YC)