The word "Rapture" is a Latin word meaning to "seize something", "snatch something", "transport something" or "suddenly by force". The word "Rapture" does not occur in the Bible, but it does describe a true Biblical event. The Rapture will include the living and dead believers in Jesus Christ.
John 11:25 "Jesus said unto her, I am the resurrection, and the life: he that believeth in me, though he were dead, yet shall he live: 26 And whosoever liveth and believeth in me shall never die. Believest thou this?"
The Song of Solomon mentions Jesus Christ calling up His Bride(the Church), who is a Gentile according to 1:5.
Song of Solomon 2:10 "My beloved spake, and said unto me, Rise up, my love, my fair one, and come away."
There are two different Raptures and the two are different because one has a trump(Church Age Rapture) and the other a trumpet(Tribulation Rapture).
The Church trump is a sound that is made by a trumpet and is the voice of God sounding as a trumpet. The voice can sound like thunder to the unsaved(John 12:29). When the Church trump is heard, the sheep hear a voice calling them home(SoS 2:10, John 10:3-4).
1 Thessalonians 4:16 "For the Lord himself shall descend from heaven with a shout, with the voice of the archangel, and with the trump of God: and the dead in Christ shall rise first:"
The Tribulation trumpet is the Angel's trumpet in Matthew 24:31 and Revelation 11. No voice is heard after the seventh trumpet blown by an angel. The only voices heard after the seventh trumpet announce that Jesus Christ is coming to reign on earth as King(Job 19, Daniel 2:35-45). Although, before the seventh trumpet there is a "great voice" that calls people up. This voice is heard near the end of the Tribulation and is directed towards Moses and Elijah.
Matthew 24:31 "And he shall send his angels with a great sound of a trumpet, and they shall gather together his elect from the four winds, from one end of heaven to the other."
Church Age Rapture - This rapture occurs before the Tribulation because the Tribulation is called "the time of Jacob's trouble". The Church is mainly Gentile, not Jewish (although both-Gal. 3:28). In 1 Thess. 4:18, Paul says to comfort saints with the words about the Rapture. There is no comfort when one thinks of going through the Tribulation.
1 Thessalonians 4:15 "For this we say unto you by the word of the Lord, that we which are alive and remain unto the coming of the Lord shall not prevent them which are asleep. 16 For the Lord himself shall descend from heaven with a shout, with the voice of the archangel, and with the trump of God: and the dead in Christ shall rise first: 17 Then we which are alive and remain shall be caught up together with them in the clouds, to meet the Lord in the air: and so shall we ever be with the Lord. 18 Wherefore comfort one another with these words."
1 Corinthians 15:51 "Behold, I shew you a mystery; We shall not all sleep, but we shall all be changed, 52 In a moment, in the twinkling of an eye, at the last trump: for the trumpet shall sound, and the dead shall be raised incorruptible, and we shall be changed."
Revelation 4:1-2 is a type of the Church Age Rapture - John is a type of the Church because he is called the disciple "whom Jesus loved". The Church is Christ's beloved(Ephesians 1:6).
Revelation 4:1 "After this I looked, and, behold, a door was opened in heaven: and the first voice which I heard was as it were of a trumpet talking with me; which said, Come up hither, and I will shew thee things which must be hereafter. 2 And immediately I was in the spirit: and, behold, a throne was set in heaven, and one sat on the throne."
Tribulation Rapture - This Rapture is primarily for the Jews/the elect (Isaiah 45:4, 65:9, 22; Daniel 7:18-27), but both Jewish and Gentile saints go up in this rapture (Rev. 7:9-12). Matthew 25 also mentions "virgins"(plural) that are to meet the Christ, while the Church is the "chaste virgin"(singular) that is to marry Christ(2 Cor. 11:2). Towards the end of the Tribulation the "elect" have requirements to see the appearance of the Tribulation Rapture. They have to be pure in heart, holy and watchful(Matthew 5:8, Hebrews 9:28, 12:14). In Revelation 14:16, Jesus is seated on a cloud during the Tribulation Rapture.
Matthew 24:29 "Immediately after the tribulation of those days shall the sun be darkened, and the moon shall not give her light, and the stars shall fall from heaven, and the powers of the heavens shall be shaken: 30 And then shall appear the sign of the Son of man in heaven: and then shall all the tribes of the earth mourn, and they shall see the Son of man coming in the clouds of heaven with power and great glory. 31 And he shall send his angels with a great sound of a trumpet, and they shall gather together his elect from the four winds, from one end of heaven to the other."
Matthew 24:40 "Then shall two be in the field; the one shall be taken, and the other left. 41 Two women shall be grinding at the mill; the one shall be taken, and the other left. 42 Watch therefore: for ye know not what hour your Lord doth come. 44 Therefore be ye also ready: for in such an hour as ye think not the Son of man cometh."
Revelation 11:15 "And the seventh angel sounded; and there were great voices in heaven, saying, The kingdoms of this world are become the kingdoms of our Lord, and of his Christ; and he shall reign for ever and ever."