[1] Besides the normal print book editions, the novel was also included on a CD-ROM sold by ClariNet Communications along with the other nominees for the 1993 Hugo awards.
The CD-ROM edition included numerous annotations by Vinge on his thoughts and intentions about different parts of the book, and was later released as a standalone e-book.
[4] The Zones reflect fundamental differences in basic physical laws, and one of the main consequences is their effect on intelligence, both biological and artificial.
Artificial intelligence and automation is most directly affected, in that advanced hardware and software from the Beyond or the Transcend will work less and less well as a ship "descends" towards the Unthinking Depths.
"An expedition from Straumli Realm, a young human civilization in the high Beyond, investigates a newly discovered five-billion-year-old data archive in the low Transcend that offers the possibility of unimaginable riches.
The expedition's facility, High Lab, is gradually and secretly compromised by an initially dormant superintelligence within the archive later known as the Blight.
The ship lands on a distant planet with a medieval-level civilization of dog-like creatures, dubbed "Tines", who live in packs as group minds.
A distress signal from the sleeper ship eventually reaches "Relay", a major information/service provider for the galactic communications network.
Ravna Bergsndot, the only human Relay employee, traces the sleeper ship's signal to the Tines' world and persuades her employer to investigate what it took from High Lab, contracting the merchant vessel Out of Band II, owned by two sentient plant "Skroderiders", Blueshell and Greenstalk, to transport her and Pham there.
The Blight expands, taking over races and "rewriting" their people to become its agents, murdering several other Powers, and seizing other archives in the Beyond, looking for what was taken.
Activating Countermeasure is fatal to Pham, but before he dies, the ghost of Old One within his mind reveals to him that, although his body is a reconstruction, his memories are real.
A race of humanoids with colorful butterfly-like wings who attempt to use the chaos wrought by the Blight to reestablish their waning hegemony.
An ancient, malevolent super-intelligent entity which strives to constantly expand and can easily manipulate electronics and organic beings.
[6] Their ancestors were "Tuvo-Norsk" asteroid miners from Old Earth's solar system, which is noted as being on the other side of the galaxy in the Slow Zone.
Each "soul" can survive and evolve by adding members to replace those who die, potentially for hundreds of years, as Woodcarver does.
Vinge's The Children of the Sky, "a near-term sequel to A Fire Upon the Deep", set ten years later, was released in October 2011.