Bradbury uses imagery in describing the dead humans as spots of paint.
Imagery is descriptive language that literally paints a picture in the reader’s mind. This mental picture is created with sensory details and figurative language, and this chilling comparison encompasses both.
The story tells of a house that carries on after its inhabitants are dead. The house is fully automated, and it does not realize that the people are all dead. The reader does not realize it either, until Bradbury slams us with a most vivid image.
The house has been burned black, and only a few spots of its original white paint remain.
Here the silhouette in paint of a man mowing a lawn. Here … a woman bent to pick flowers. Still farther over … a small boy, hands flung into the air … and opposite him a girl, hands raised to catch a ball which never came down.
The family was caught and captured in this “titanic instant” when the bomb blast hit. Their images were burnt into our minds, because they shielded the house and created perfect silhouettes of their last moments alive. They will forever remain a father mowing the lawn, a mother picking flowers, and a brother and sister playing catch.
Authors use imagery to help the reader get the point. Here, the point about the danger of relying on technology is clearly made. We create things to make our live easier, but we can only hope to avoid being the victims of our creations.
For more, see: http://www.enotes.com/topics/literary-terms/in-depth Scroll down to imagery.