The most important image in The Great Gatsby is the color green. It is the color of America, Fitzgerald tells us, when the Dutch first landed here; the color of money, certainly; and the color that says "go," that most American of injunctions. At the edge of Daisy's dock, famously, there is a flashing green light, which Gatsby can see from his mansion. When Nick first encounters Gatsby, he is alone, holding his hands up toward that light, the bright, shining embodiment of his ideal of Daisy.
The enigmatic central figure, he is a mid-western boy, born James Gatz, who was a poor drifter as a youth. As a young soldier he falls in love with . After World War I he builds a fortune as a bootlegger, and tries not simply to win her back, but to eradicate the time between (and her marriage) as if it had never been. He is a romantic figure, but an egoist who is totally self-obsessed, unable to live outside the seductive dream-world he has created. At the same time, there is an odd kind of innocence about his delusion, and he is capable of acting with integrity and even a certain greatness. (Chambers dictionary of literary characters.)
The narrator, he is a young mid-westerner who has come east to work, and is sucked into 's seductive orbit because is his cousin. He is sensitive, intelligent and cultured, and rejects the immoral blandishments around him, and the superficial values of the Long Island set. We see Gatsby through his eyes, and his rectitude sets the tone for the novel, but he is tolerant and non-judgemental in his assessment of him. (Chambers dictionary of literary characters.)
A Southern belle who was loved by when he was a younger man, but who has married for his wealth. Beautiful, with ‘an excitement in her voice that men who had cared for her found difficult to forget’, she is embittered by her husband's infidelities, but remains fun-loving and flirtatious despite her disillusion. She allows herself to enter into Gatsby's dream, but is quick to retreat into the shelter of Tom's wealth and their shared indifference after his death. (Chambers dictionary of literary characters.)