Samwise Gamgee, sometimes called Sam, was the son of Hamfast, the gardener of Bag-End. When Hamfast grew old Sam took care of Bag-End and thus came to know Bilbo, who would often tell him stories of Elves, a race which he always had a desire to see for his entire life. He soon met Frodo, and later became his servant and best-friend.
In 3018 Sam was chosen by Gandalf to accompany Frodo to Rivendell. He sneaked into the Council of Elrond in Rivendell and was therefore chosen as a Companion of the Ring. After the breaking of the Fellowship of the Ring only Samwise Gamgee went with Frodo into Mordor. In the Pass of Cirith Ungol Frodo and Sam were attacked by Shelob, and Sam, taking up Frodo's sword Sting terribly wounded Shelob, and posibly killed her. Thinking Frodo dead, he took the One Ring from his body and journeyed into Mordor alone. On the way to Orodruin he was forced to carry Frodo much of the time, for the weight of the Ring was overpowering Frodo. Sam witnessed the doom of the Ring firsthand, for he was there when Gollum attacked.
After the War of the Ring Sam returned to Hobbiton and married Rosie Cotton, and later they had thirteen children together. Sam dwelt in Bag-End from 3021 forward, until the death of Rosie in 82 of the Fourth Age, (between these two events Sam became the mayor seven times) he sailed over the Sea. Had he not borne the Ring for a time he would not have been permitted to go.
Gamgee is not pronounced according to the usual pronounciation methods, for it is more similar to Gamjee, simply because the name is a shortened form of Gammidgy.