The Jedi Temple was the center of the Jedi Order, stationed on the planet Coruscant, from the conclusion of the Great Sith War to the Great Jedi Purge and during that time was home to its major training, bureaucratic and dormitory facilities. This Facility was a kilometer high, and had a total of five spires on top. The center Spire held the Hall of Knighthood. The other four Spires held a seperate Jedi Coucil, these included the Jedi High Council, Council of First Knowledge, Council of Reconciliation, and the Reassignment Council. The spires all had Transmitter Antennas, in each of the five spires, so, this is why that the Spires, and the whole building is above the other buildings in Coruscant.
The Jedi Temple was the home of the Jedi Council.
There were also many Jedi Enclaves, such as the one on Dantooine, which served as lesser Temples.
After the Great Jedi Purge, the Temple on Coruscant was destroyed. However, Luke started a new temple after the Empire was destroyed on Yavin 4.
The Library section of the Jedi Temple