Amoraim ("expounders"): The sages of the Talmud who were active during the end of the era of the sealing of the Mishnah, and until the times of the sealing of the Talmud (220CE500CE).
The commentators of the Talmud: Scholars who lived at the end of the period when the Mishnah was compiled and until the time when the Talmud was finalized.