Tanakh is the Jewish name for the Hebrew Scriptures, what Christians call the Old Testament. The word itself is an acronym standing for three words: Torah (the Pentateuch), Nevi’im (Prophets, pronounced n’-vee-eem), and Ketuvim (Writings, pronounced k’-tu-veem). The last two sections, Nevi’im and Ketuvim, can be called Nakh, but this term is primarily used in religious Jewish circles.
Although the contents of the Tanakh are identical to the contents of the Old Testament, the books are organized differently, following slightly different conceptual lines. The order of the books that is familiar to most Christian readers follows the Septuagint tradition and is divided as follows: Law (the five books of Moses); History (Joshua-Esther); Poetry and Wisdom (Job-Song of Solomon) and Prophets (Isaiah-Malachi, including Daniel and Lamentations).
The order of the biblical books in the Tanakh is broken down into three main categories:
Torah: The five books of Moses; this is identical to the “Old Testament” order, but the books are named after the opening word of each book, and so Genesis is Bereshit, pronounced b’-rey-sheet; Exodus is Shemot, pronounced shey-moht, taken from the second word of the text, names; Leviticus is Vayikra, pronounced, va-yik-rah; Numbers is Bamidbar, pronounced bah-mid-bar; and Deuteronomy is Debarim, pronounced d’-vah-reem, taken from the second word of the text, words. For more discussion of the term Torah, see #5.
Prophets: This section is divided into the “Former Prophets”—referring to Joshua, Judges, 1-2 Samuel and 1-2 Kings, based on the belief that these books were all written by prophets—and the “Latter Prophets”—referring to Isaiah, Jeremiah, Ezekiel and Hosea-Malachi, called “The Twelve.”
Writings: This includes all the remaining books, generally in the following order: Psalms, Job, Proverbs, Ruth, Song of Solomon (normally called “Song of Songs,” and based on the opening verse), Ecclesiastes (normally called Koheleth, meaning “the preacher” or “convener,” based on the opening verse), Lamentations (called Eichah, meaning “how, alas” which is the opening word of the book), Esther, Daniel, Ezra, Nehemiah and 1-2 Chronicles.
Reading through portions of the Scriptures is a fixed part of Jewish liturgy, with the greatest emphasis put on the Torah, which is read through in its entirety in the synagogues over the course of every year. This is supplemented each week by a reading from the Nevi’im (Prophets), called the Haftarah (meaning supplement, commonly pronounced Haftorah), while other portions of Scripture, especially the Psalms, are included in the daily prayers.
There are other, special readings for various holy days, most notably the reading of what are called the Five Scrolls (Hebrew, chamesh megillot) on five of the major holy days. The Five Scrolls are the Song of Songs (or Song of Solomon), which is read on Passover (pesach) to commemorate God’s love relationship with His people; Ruth, which is read on Shavuot (Pentecost) because of the harvest imagery; Lamentations (called Eichah, based on the opening word, How), which is read on Tisha b’Ab (the Ninth of Av, the ultimate day of mourning on the Jewish calendar); Ecclesiastes (called Kohelet, based on the Hebrew word found in Ecclesiastes 1:1, meaning, “the preacher” or “the convener,” and translated “teacher” in the NIV), which is read on Sukkot, Tabernacles, in recognition of the transitory nature of life); and Esther, which is read on Purim, whose background is given in Esther 9:26-32.
Because the majority of Jews worldwide today are not observant (in fact, roughly 90 percent are not Orthodox; see #1), most of them are not familiar with their own Scriptures. In contrast, observant Jews tend to be very familiar with the portions of the Tanakh that are part of their liturgical and study cycle but not as familiar with other portions of the Tanakh, since they primarily study the Talmud and related legal literature.
As for the use of acronyms (as in Tanakh), it should be noted that there are literally hundreds of such acronyms in Judaism, and so Rabbi Moses ben Maimon (Maimonides) is called Rambam (based on the letters R-M-B-M) and Rabbi Moses ben Nachman (Nachmanides) is called Ramban (based on the letters R-M-B-N). Similarly, Rabbi David Kimchi is called Radak (based on the letters R-D-K) and Rabbi Levi ben Gershom is called Ralbag (based on the letters R-L-B-G).
For answers to many other, related questions, see Dr. Brown’s recent book 60 Questions Christians Ask About Jewish Beliefs and Practices