SF is difficult to define. Roberts offers a few perspectives.
SF is a genre that rationalizes its differences in a physical (or, one might say, scientific) way:
Roberts introduces Darko Suvin's idea of the novum:
Roberts also describes Robert Scholes's definition of SF from his book Structural Fabulation, though his description doesn't do much service to it.
Finally, Roberts offers a definition from Damien Broderick, summarizing:
There is a common theme:
Roberts concluces with a case study of Dune.
Chapter 2: The History of SF
A familiar history, touching on proto-sf from the classical period and a few scattered thoughout history, before settling on the usual starting point of Frankenstein, and proceeding through Verne and Wells.
Once into the modern period, Roberts discusses SF as embodied in the pulps, the Golden Age of SF, and the New Wave.
Roberts concludes with a case study of Star Wars with a focus on intertextuality.
Chapter 3: SF and Gender
The Left Hand of Darkness
Star of Danger
The Female Man
When It Changed
Banner of Souls
Woman on the Edge of Time
The Women Men Don't See
The Girl Who Was Plugged In
I'll Be Waiting for You When the Swimming Pool Is Empty
The Girl Who Was Plugged In
...lots of Tiptree
The Image of Women in Science Fiction
Neveryon / Delany
Titan; Wizard; Demon / Varley
The Ship Who Sang
Is Gender Necessary? (see also Is Gender Necessary? Redux)
Discusses the Alien films as associating the alien with women.
Chapter 4: SF and Race
This chapter has some interesting things to say, but in short SF does address issues of race, and insofar as race is a fundamental kind of difference with which society is concerned, it is implicit in SF narratives in general, in much the same way as the issue of gender.
Case study: Butler's Xenogenesis trilogy
Kindred / Butler
Starship Troopers / Heinlein
A Cure for Cancer / Moorcock
The Land Leviathan / Moorcock
Farnham's Freehold / Heinlein
The Einstein Intersection / Delany
Chapter 5: SF and Technology
Roberts asserts: "The spaceship is almost always humanised; it may be sentient itself [...] or, at the very least, imbued with a certain character and individuality, like Millennium Falcon in Star Wars." Isn't that going quite too far? I don't think there's anyone who would agree that the MF is in any way humanised, and 'it has a certain character' is too weak an argument for that proposition.
Roberts makes the point, not very well, that spaceships can be characters or otherwise fill roles beyond mere props.
Roberts discusses robots, which may function as a metaphor for race, or for sex or some other division of people, or may act as a commentary of something more basic: what it means to be alive, to have purpose, etc.
Roberts then enters into an extended discussion of Star Trek's Borg, which I think is not entirely well-advised at this point. He argues that the Borg represent a truly alien culture, with values really incompatible with human ones, not in the sense of being opposed to ours, but rather existing separate from ours. Sure, but this has little to do with robots, cyborgs, or even technology, so it's not well-placed at this point in the book.
Case study: Neuromancer.
Port Eternity / Cherryh
Culture series / Banks
The Ship Who Sang / McCaffrey
2001 / Clarke
Merchanters series / Cherryh
NonStop / Aldiss
Confluence series / McAuley
R.U.R. / Capek
Westworld (film) / Crichton
Chapter 6: Conclusion
More about what sf is, how it works, etc., primarily concerned with metaphor.