Strictly speaking, every science fiction tale presents its own version of future and therefore there are as many science fiction universes as there are science fiction stories. Many SF tales follow dictates of a particular subgenre like Cyberpunk or Space Opera of which, see the separate entry.
... someone living alone who is 65 years of age or older. The average household size is 2.86 and the average family size is 3.32.
In the town the population is spread out ...