Abomination of Desolation: A future incident when Antichrist enters into the rebuilt Jewish temple and declares himself to be God. (Dan. 9:27, Matt. 24:15, 2 Thess. 2:3-4). This occurs in the exact middle of the 7-year tribulation period.
Antichrist: A future dictator who attempts to control the world just prior to the Second Coming of Christ (2 Thess. 2:3-9).
Eschatology: The study of end-time events.
Millennium: The 1,000 year reign of Christ upon earth which follows the Second Coming (Rev. 20:2-4).
New Earth: After earth is destroyed at the end of the Millennium, God will create a new (atmospheric) heaven and a new earth which will last for eternity (Rev.21:1, Isa. 65:17, 66:22, 2 Pet. 3:10-13).
New Jerusalem: The heavenly city, which will come down out of heaven to the New Earth, after this present earth is destroyed (Rev. 21:1-2, 10-27).
Rapture: When Jesus returns in the clouds to receive the church into heaven (John 14:1-3, 1 Thess. 4:13-17). Those Christians who have died will be resurrected and those who are alive will be instantly translated into glorified bodies (1 Cor. 15:51-54). This is not the same event as the Second Coming.
Second Coming: When Jesus returns from heaven to earth at the Mount of Olives in Jerusalem (Zech. 14:1-3, Rev. 19:11-21).
Tribulation: The final 7 years before Christ returns to earth at the Second Coming. Begins when the Antichrist confirms a 7-year covenant with Israel. The tribulation is split into two halves of 3 1/2 years each, divided in the middle when the Antichrist stops the sacrifices in the temple (Dan. 9:27). The 3 1/2 years are also referred to as 1,260 days (Rev. 11:3, 12:6), 42 months (Rev. 11:2, 13:5), and time, times, and a 1/2 time (Rev. 12:14, Dan 7:25, 12:7).