Tanakh is a 3-letter hebrew acronym. An approximate English spelling would be "TNK".
TNK stands for Torah, N'viim, and K'tuvim. Torah means the five books of Moses, N'viim means the Prophets, and K'tuvim means "Writings" (includes Psalms, Proverbs, the book of Job, the book of Ruth, the book of Esther, etc).
The books of the Tanakh are at the core of religious
Jewish belief. Other Jewish writings, such as the
Mishnah and
Talmud build and quote from the lessons and stories found in the Tanakh.