First rabbinical era; refers to the period when five successive pairs (zugot) of legal scholars ruled the Beit Din HaGadol (the Jewish supreme court).
The five pairs of zugot are:
• Jose ben Joezer + Jose ben Johanan
(Maccabean period)
• Joshua ben Perachyah + Nittai of Arbela
(John Hyrcanus period)
• Judah ben Tabai + Simeon ben Shetach
(Salome Alexandra period)
• Sh’maya + Abtalion
(Hyrcanus II period)
• Hillel + Shammai
(Herod the Great period)
The (macro) rabbinical eras are:
Zugot – just–described
Tannaim
Amoraim
Savoraim
Geonim
Rishonim
Acharonim