The Pedestal of Time first officially appeared in The Legend of Zelda: Ocarina of Time, though a similar, if not the same, pedestal also appeared in The Legend of Zelda: A Link to the Past years earlier. It is the resting place of the Master Sword and has become a major part of the plot in the games it's appeared in. In Ocarina and Twilight Princess it was located in the Temple of Time.
As aforementioned, it's possible that the pedestal actually appeared in A Link to the Past first, as a dramatically similar pedestal was present in the Lost Woods. Just as in Ocarina, Link was required to come in possession of three sacred objects in order to wield the Master Sword and ultimately pull it fro the pedestal. The sole theory that this may not in fact be the Pedestal of Time is the fact that it's not located in the Temple of Time.
In it's first official appearance (in name), it appeared in Ocarina of Time. You'd be given access to the Master Sword once you collected three stones (similar to the objective in A Link to the Past).