Sundering of the Elves

In J. R. R. Tolkien's legendarium, the Elves are a sundered people. They awoke at Cuivienen on the continent of Middle-earth (see: Awakening of the Elves), where they were divided into three tribes: the Vanyar, the Ñoldor, and the Teleri. After some time, they were summoned by Oromë to live with the Valar in Aman. That summons and the Great Journey that followed split the Elves into two main groups (and many minor ones), which were never fully reunited.

The name Quendi refers to all elves.

Avari
The Avari are Those who Refused the Summons of Oromë, or simply The Unwilling. (Most of the Avari came from the largest tribe, the Teleri. A few of the Ñoldor remained as well, but were no longer called by that tribal name.) Together with the Nandor and the Sindar, they are called the Moriquendi (Elves of Darkness) in recognition of the fact that they did not see the light of the Two Trees. While all of the Eldar departed Middle-earth by the early Fourth Age, it appears that the Avari mostly stayed.

Eldar
The Eldar are those who accepted the summons. Their name, literally Star People, was given to them by Oromë in their own language. Those of the Lindar who undertook the Great Journey were called the Teleri.
 * Those of the Teleri who refused to cross the Misty Mountains, and stayed in the valley of Anduin, are called the Nandor (Valley People).
 * Those of the Nandor who left the Anduin under the leadership of Denethor and came to Beleriand are called the Laiquendi (Green Elves).
 * The other Nandor became known as the Silvan Elves, living in the forests of Wilderland. They were joined there by some of the Avari.
 * Those of the Teleri who reached Beleriand by the Great Sea but chose not to cross to Aman were called the Sindar (Grey People).
 * Many of the Teleri chose to remain behind in order to look for their lord Thingol, who disappeared near the end of the journey. These were known as the Eglath (Forsaken), because they were left behind when their kindred crossed the Sea.
 * Those of the Teleri who came to the shores of the Great Sea but decided to stay there are called the Falathrim (People of the Shore).
 * The Vanyar, the Ñoldor, and those of the Teleri who stayed with them to the end are called the Calaquendi (Elves of Light) because they saw the Two Trees. The rest of the Teleri are also sometimes counted among the Moriquendi.
 * Most of the Ñoldor returned with Fëanor to Middle-earth, and at least some of these remained there through the Third Age. These became known as the Exiles.
 * Those Ñoldor that remained behind or returned under Finarfin became known as the Aulendur (Servants of Aulë).



Eldar