Rannoch

Rannoch (pronounced RAN-nokh) is a planet within the Tikkun System. It is the homeworld of the quarians, and later the geth (though the geth do not actually live on the quarian worlds, they simply function as caretakers). Its name in ancient Khelish means "walled garden", though nowadays the quarians simply call it the homeworld. It is notable for having no insect life; as such, pollinating plants have evolved a symbiosis with higher order animals. This is considered a contributing factor to the quarians' weak immune systems, since infections could just as well have been beneficial as they were harmful, and the quarians were more likely to just simply adapt to them.

According to Legion, an advanced geth mobile platform, Rannoch is more arid than Earth, and its star is older, making it more orange than Sol. The mobile platforms operating on Rannoch and other quarian worlds clean rubble and toxins left over by the Morning War, in memoriam to the quarians who died. The geth themselves live in space stations, where they can mine nearby asteroids. Commander Shepard can comment that the closest equivalent from human society is a memorial cemetery or battlefield.

Mass Effect 3
In Mass Effect 3 Commander Shepard will visit Rannoch, where the quarians are in the process of attempting to retake the planet.