There is a whole period between 200 BCE to 500 CE when the great work of reducing the "Oral Torah" tradition (Torah shebeal pe) to written documents, took place. From 200 to 20 BCE, what is called the "Pre Tannaim", a semi organized effort to accumulate and write down the oral tradition and the oral interpretation of the Torah took place. It is characterized by "pairs" (zugot) of sages arguing various pro and con for each interpretation and their students writing and copying these arguments down. Then came the period of the "Tannaim", and they are classified as six generations of Tannaim, from 20 BCE to 200 BCE, ending with the final redaction of the Mishna by Yehuda HaNasi in 200 CE. There is a short transition of about 20 years (200-220 CE) before the eight generations of the Amoraic period (the True "Talmudic period") from 200 to 500 CE finishes the work of interpreting the Mishna in the form of Gemara (in essence putting an end to arguments about various open issues). The Amorai where divided into two main centers of study, the Babylonian (Babylonian Talmud) and the Israeli center. (Jerusalem Talmud, though most of the Jerusalem Amorais really lived in the Gallilee).
Note how unique is the history of that Jewish nation, they mark periods in their nation's history by the development of their codex of law, not wars and conquests, nor the subjugation of others, but the extent of the development of their holy essence, their moral code, the Torah.
The Torah is the essence of the "law", the Mishna, is organized in six major orders is a series of very short, almost terse statements requiring interpretation, the Amorais added such interpretations in the "Gemara" and the Talmud is in essence a compilation of the Mshan and the Gemara text organized in about sixty six tractates. In essence it is a collection of both legal precedences (many of the discussions are actually related to property dispute, agricultural law, wedding law, tithes, fixing the times for festivals etc.).
Zeev