What is the meaning or theme of the story "Harrison Bergeron" and how are the characters relevant to that meaning?

I assume by meaning that you want the main theme of the story. I would say that Vonnegut, the author, is showing us what happens in a society where competition is no longer allowed because the government has decided what is "normal" and what isn't. Anyone who is considered to be above normal, like Harrison and his father, is handicapped. No one who is less than normal should ever feel bad about him/herself. Society has become one of mediocrity, keeping everyone as close to the same both physically and mentally. Hazel, Harrison's mother, illustrates those in society who are below average, and she doesn't have to wear any handicaps. Harrison is, of course, the superman of society, both physically and mentally. He cannot be allowed to live once he tries to overthrow the government's control.

Vonnegut also shows the effect of the broadcast media on society. The Handicapper General uses radio signals to punish those who think the wrong thoughts or say the wrong things. He depicts television as having a numbing effect on people, to the point that they are desensitized by what they see. Hazel can't even remember that her son has been killed right in front of her.

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