What we call the Old Testament consists of:
The Torah: The Five Books of Moses
The Nevi’im: The books of the Prophets
Ketuvim: The Writings
The Hebrews call these collecting writings the Tanakh; and we call them the Old Testament.
In these Scriptures, we see the history of the Jewish people, and more importantly, the prophecies of the coming Moshiach (Messiah).