The Hebrew word "moshiach" means annointed one. There have been many moshiachs throughout Jewish history. Every Jewish king and priest was a moshiach. There was even a non-Jewish moshiach (King Cyrus who permitted the rebuilding of the Temple). The Jewish Messiah will be a man and not a demi-god. He will come once and only once there will be no "second coming". The belief in an eventual moshiach (Moshiach ben David - Moshiach, son of David) who will be the last king and ruler of Israel is an ancient belief. There is a belief that a potential moshiach is born in every generation. Most scholars believe that it is the conduct of humankind that will determine when the moshiach will arrive.

Who Will the Moshiach Be?
(1) He must be Jewish (Deuteronomy 17:15; Numbers 24:17);
(2) He must be descended from David through Judah (Genesis 49:10) and Solomon (I Chronicles 22:9-10; Jeremiah 23:5; Ezekiel 34:23-24, 37:21-28; Isaiah 11:1-9; Jeremiah 30:7-10, 33:14-16; Hosea 3:4-5);
(3) He will be well-versed in halachah and will observe the mitzvot (Isaiah 11:2);
(4) He will be the perfect judge able to see beyond words and appearances (Isaiah 11:2-3);
(5) He will be able to vanquish evil at a word (Isaiah 11:4);
(6) He will be the king of an independent and recognized Israel (Isaiah 11:10);

What Will Happen When the Moshiach Arrives
(1) Elijah will proceeded the Moshiach and announce his arrival (Malachi 3:23-24)
(2) With the coming of the Messiah will be the physical ingathering of Judah from the four corners of the earth (Isaiah 11:12, 27:12-13, 43:5-6; Jeremiah 16:15, 23:3; Zechariah 10:6; Ezekiel 37:21-22;
(3) There will be the reestablishment of the Holy Temple (Micah 4:1; Ezekiel 37:26-28; Isaiah 33:20);
(4) There will be world-wide peace (Isaiah 2:4, 11:6; Micah 4:3; Ezekiel 39:9);
(5) In the Messianic age the entire world will believe in G-d (Isaiah 2:4, 11:9, 40:5; Zephaniah 3:9; Jeremiah 31:33; Zechariah 8:3, 14:9,16;
(6) The Jews will be sought for spiritual guidance (Zechariah 8:23);
(7) Death will cease (Isaiah 25:8) and the dead will be ressurected (Isaiah 26:19; Daniel 12:2; Ezekiel 37:12-13);
(8) The enemy dead will be buried (Ezekiel 39:12);
(9) The Nations will help the Jews materially (Isaiah 60:5,10-12, 61:6);
(10) Each Tribe of Israel will receive its inheritance (Ezekiel 47:13-14);
(11) Eternal joy and gladness will characterize the Jewish Nation (Isaiah 51:11);
(12) The Egyptian River will run dry (Isaiah 11:15);
(13) Trees will yield new fruit monthly in Israel (Ezekiel 47:12);
(14) The nations will recognize the wrongs they did to Israel (Isaiah 52:13-53:12);
(15) Israel will be perfect in the practice of Torah (Deuteronomy 30:6; Jeremiah 31:31-33);
(16) All of Israel will be prophets (Joel 3:1-2);
(17) The Messiah will be universally recognized (Isaiah 11:10)

This is only a partial list of the requirements.