There are many symbols in The Giver, because the story itself is largely symbolic. Three examples are the apple, memories, and the sled.
[Following] the path of the apple through the air with his eyes, that the piece of fruit had—well, this was the part that he couldn't adequately understand—the apple had changed. Just for an instant. It had changed in mid-air, he remembered. (p. 24)
The apple is a symbol of life. It is linked to real emotion, because it is a real color. When Jonas sees the color red for the first time, this is the first time he realizes he is different. As Receiver of Memory, he will begin to learn about emotions. The apple is his window into the world of human experience. This makes him unique, because no one else in the community feels things—except The Giver.
"All I gave you was one ride, on one sled, in one snow, on one hill. I have a whole world of them in my memory. I could give them to you one by one, a thousand times, and there would still be more." (p. 83)
The memories are a symbol of hope. Memory functions in the community much as it does in our world, but differently at the same time. Memories of history are gathered collectively and passed down through those special individuals who are the Giver and Receiver of Memory. The Giver, who does not have a name, is able to transmit memories to Jonas of the way the community was before Sameness. Through the memories, Jonas learns real human emotions. This gives him hope for a better life, for himself and for his people. They give him the courage to leave.
Sled, he knew abruptly. He was sitting on a thing called sled. And the sled itself seemed to be poised at the top of a long, extended mound that rose from the very land where he was. Even as he thought the word "mound," his new consciousness told him hill. (p. 81)
The sled is the first memory that Jonas receives, and it is red, connecting it to the apple. The first memory is a pleasant one. Jonas enjoys the sled ride, and asks why there is no longer snow. The sled is a symbol of freedom. In the world where the first memory comes from, sledding is fun and snow is enjoyable. Eventually, Jonas escapes to elsewhere on a sled.
Through the use of symbols such as these, Lowry reinforces the major themes of the book: identity, individualism, and the importance of human emotions.
Lowry, Lois (1993-04-26). The Giver (Newbery Medal Book). Houghton Mifflin Harcourt. Kindle Edition.