Hebrew/Jewish Bible numbers 15 Prophets: Isaiah, Ezekiel, Jeremiah and "The Twelve". The Book of Daniel is part of the Ketuvim (Writings).
The Christian Old Testament contains 16 Prophets: 4 Major, 12 Minor
Prophets are messengers of God's revelation
Prophet "nabi" - comes from an old root "n-b-'" meaning "to call, to summon up, to speak on behalf of" - this could refer to the prophetic call (God calls his prophets to be his messengers) or the prophet "calling/summoning up" the people and "speaking" on behalf of God
Prophets can be divided into:
Non-writing Prophets (sometimes called Primitive Prophets)
Begins with Moses and continues with other non-writing prophets like Samuel, Nathan, Gad, Elijah, Elisha
Writing (Classical) Prophets
Those with books in the Old Testament
Emerged in 8th Century BC in both Kingdoms
Prophets Can be divided Chronologically
8th Century BC Prophets (North: Hosea, Amos; South: Isaiah, Micah)
7th Century BC Prophets
7th-6th Century BC Prophets
Exilic Prophets
Post-Exilic Prophets
8th Century BC Prophets
Context
Rise of Assyria
Tiglath-Pileser III (734 BC, the Syro-Ephraimite war; Isaiah and king Ahaz of Judah (Isaiah 7))
Sargon II (722 BC, the fall of Samaria and exile; King Hoshea of Israel)
Sennacherib (701 BC, the siege of Judah and Jerusalem; King Hezekiah of Judah)