All these series including, the Lord of the Rings, the War of the Ring, the Ring Quest, the Fellowship of the Ring begin, revolve around an important thing, Ring. Therefore, you can safely say that Ring is really very important symbol in aforementioned series. In fact, it symbolizes power, control and makes an influence on people and things. This symbol has no value to those, who do not care actually about power. It stands for power in any form, whether with having good intentions or bad ones.
What the Ring symbolizes in “The Fellowship of the Ring”