The Zones of Thought is a science-fiction setting created by Vernor Vinge.In the Zones of Thought verse, the basic gimmick is that the Singularity is spread out sideways. In the Unthinking Depths near the core of the galaxy, no intelligence is possible; in the Slow Zone, where Earth is, Mundane Dogmatic rules apply; the Beyond allows soft SF tropes such as faster than light travel or antigravity, and in the Transcend, everyone is sufficiently advanced. Thus, as you head out of the galaxy, you see the same progression of advancing technologies as you'd expect to see over time if our technology went through a Singularity. In the Slow Zone, Vinge posits that human technological advance reached an apex with the "Age of Failed Dreams", during which it was discovered that faster than light travel, immortality, strong AI, and a few other things are impossible.A Deepness in the Sky takes place in the Slow Zone, next to a very peculiar star. Humanity ignored it for centuries, until possible alien radio signals prompt two nearby cultures to each send a fleet of ships: the Qeng Ho, part of a group of interstellar traders, and the Emergents, an enigmatic civilization that has suddenly raised their technology to high levels.A Fire upon the Deep, which was written first, mostly takes place in the Beyond. A human expedition to the Transcend releases the Blight, a malignant artificial intelligence which has been dormant for five billion years. The only survivors of the expedition are one family, who flee to a backwater world, where both parents are immediately killed and the children sucked into the power struggles of the medieval-level alien natives. Meanwhile, the Blight is rampaging across the galaxy, so a second expedition is sent in search of the children, on the off-chance that their parents might also have found a counter-measure.The Children of the Sky, a sequel to A Fire Upon the Deep, came out in October 2011.
Alternate Number System: The Tines have two different number systems: one where they count "by legs" (in base 4) and one where they count "by fore-claws" (in base 10). Confusion between these two systems leads to the accidental meeting of two of the major characters in A Fire Upon the Deep. Amdiranifani is housed in room 33, Jefri is supposed to be imprisoned in room 15 (33 in base 4), and the guard who's taking him there uses the wrong numbering system.
Apocalypse How: A Fire Upon the Deep features a mind-boggling amount of death and destruction. It's strange sort of Class X-3: While most of the good guys survive, and so does the planet on which most of the novel unfolded, an enormous area of High Beyond is converted to Slow Zone. This destroys the Blight, which is dependent on High Beyond technology for its survival. It is also the deathblow for trillions of beings and countless civilizations across a huge swath of the galaxy, whose existences depended on FTL and the same advanced tech as sustained the Blight.
While it was said that trillions were killed in this act, if you look at the visualization of the galaxy and it's zones, the area affected is relatively small in comparison the totality of the Beyond.
Ancient Conspiracy: A Fire Upon the Deep contains an extremely dormant trap setup by the Blight the last time it was active, billions of years ago.
Author Tract: A Deepness in the Sky often veers in this direction, particularly whenever there are comparisons between the Emergent civilization and Qeng Ho.
Batman Gambit: A Deepness in the Sky has a rare example of competing protagonist Batman Gambits. Sherkaner Underhill invaded the Focus system and manipulated it to defend against Nau's genocidal plans, while Pham Nuwen used the localizers to invade the system and manipulate it against Nau. They both almost squash each other by accident, buying Nau valuable time when executing his Evil Plan and leading to the probable death of both Sherkaner and his wife.
Big Brother Is Watching: In A Deepness in the Sky, the Emergents take over the Qeng Ho ships, using thousands of dust sized cameras to watch over the Qeng Ho.
She spends 5 or 6 years aboard a star ship, isolated from her peers with only a low-population skeleton crew for company. Of course, Qiwi and her parents find this a fun learning experience.
Later, the older Lisolet (Qiwi's mom) is killed in rather gruesome (or serene, your mileage may vary) scene.
A work crew is seemingly cooked alive as soon as OnOff enters its 'On' state. Qiwi remarks, "I should have been there."
Not to mention the fact that, every so often, she learns the horrible truth about her situation- particularly the scene where she stumbles upon a recording of Thomas Nau enjoying torturing her mother to death- just to have her mind wiped. Again and again and again.
In A Deepness in the Sky, Pham Nuwen and Tomas Nau.
In A Fire Upon the Deep, Flenser. (Probably The Woodcarver, too; Flenser was her student originally.)
In Children of the Sky, Vendacious reprises his role and pulls a Dragon Ascendant between books to have a go at a bit of the old game.
Consummate Liar: Tomas Nau. The old Flenser once was this too, noting, that his previous self could have convinced a fish to swim right into his mouth, but during the story he's no longer able to maintain his facade consistently, thanks to Tyrathect's influence.
The Cuckoolander Was Right: In A Fire Upon the Deep, there's a galaxy-spanning Usenet-like network where various aliens discuss the crisis, from a number of different perspectives. One particular alien, "Twirlip of the Mists", is talking through several layers of auto-translation software on an extremely low-bandwidth connection, so most of what it says sounds rather bizarre. It's pretty much all exactly right, though, including such apparent nonsense as "hexapodia is the key insight".
Crazy-Prepared: Pham Nuwen in A Deepness in the Sky. For centuries he has been collecting the most advanced technologies from around the galaxy for his own personal arsenal of tricks. He put secrets into the standard design and equipment of Queng Ho ships that nobody else knows about, and which have layers of innocuous disguises.
Deceptive Disciple: Flenser was Woodcarver's offspring/creation and most brilliant disciple, until the nature of his experiments was revealed. Some characters including Flenser!Tyrathect even call out Woodcarver for creating such a monster and then just letting him go.
Downer Ending: If you read both A Fire Upon The Deep and A Deepness in the Sky, you realize that at the end of A Deepness in the Sky, Pham Nuwen points his fleet towards the unthinking depths of the galaxy, where (most likely) everyone dies in a futile attempt to learn the wonders of the galaxy — which happen to lie in the opposite direction. Pham Nuwen gets reassembled thirty thousand years later.
Dramatic Irony: The end of A Deepness in the Sky. Such dramatic irony. Pham has stumbled onto the secret of the galaxy's construction, except he has it backwards. Oops.
Dying Like Animals: Reactions to The Blight in A Fire upon the Deep mostly fall into various types of this - most of the Beyond civilizations are either Ostriches or Mice, depending on their proximity to The Blight's domain (granted, this is somewhat excusable, when the threat is a malevolent Physical God among gods and there is almost nothing you can do anyway), Powers are Bats, at least until the death of the Old One, and Aprahanti are nothing but Weasels.
Earth-Shattering Kaboom: Wars in Beyond are fought with antimatter bombs and relativistic-speed kinetic projectiles, so these do happen.
Evilutionary Biologist: Flenser, sort of. The science on his world isn't nearly advanced enough to provide knowledge of genetics, but unique physiology of his race and complete lack of anything resembling morals or empathy allowed him to get really, uh, creative with literally constructing his subjects to his specifications.
Fantastic Racism: Both of the main villains in The Children of the Sky are racist towards each other's respective races. This, curiously, does not stop them from cooperating.
Fate Worse Than Death: Being controlled by the Blight and being a Skroderider. The victims remain fully conscious, but have absolutely no ability to resist, and can only watch as the digital Eldritch Abomination uses their bodies and minds as its eyes and hands. One of the characters gets temporarily overtaken and then freed from control, thanks to the special circumstances. Her reaction is several hours of mute shock, followed by screaming breakdown.
Faux Affably Evil: Tomas Nau and particularly Flenser. In fact, master villains can be distinguished by ability to be charming and polite up to the moment Cold-Blooded Torture starts, and maybe even after, while inferior underlings and pretenders have trouble hiding their true nature.
Fighting from the Inside: A rare villainous example. Flenser struggles to suppress personality traits of Tyrathect and take complete control over their Hive Mind. He fails without realizing it, but gaining a conscience proves to be not a bad thing after all.
Gambit Pileup: In A Deepness in the Sky, Sherkaner Underhill and Pham Nuwen accidentally steamroller each other with their simultaneous Batman Gambits, giving Nau an opening to execute his own plan and nearly kill them all. He fails, but at the possible cost of Sherkaner and his wife's life, as well as many of his friends and staffers.
Giant Spider: A Deepness in the Sky features a whole race of them, and they LOVE humans. (Specifically, they think humans are absolutely adorable. Our big, googly eyes remind them of their own children.)
Good Is Not Dumb: Woodcarver, Ravna Bergsndot, Sherkaner Underhill... in fact, good damn well should not dumb to prevail in this universe.
Have You Told Anyone Else?: In A Fire Upon the Deep, when Scriber discovers a weak point in Woodcarver's security and points it out to her intelligence chief — who turns out to be the double agent who created and makes use of the weak point.
Heel Face Turn: Flenser/Tyrathect - there is a room for doubt about his sincerity, to be honest, but other characters decided to believe him. A number of lower-caste Emergents might count, although they weren't really evil (rather than brainwashed and manipulated) to begin with.
Human Popsicle: Used by the Qeng Ho in A Deepness in the Sky, so they can survive the several century long voyages on their ramscoop ships.
Humans Are Special: Averted. Humans are not special at all. Well, except Pham Nuwen, who is so awesome that a Physical God who was as above normal sapients, as they are above fish, admitted to not being able to invent a personality like his.
it wasn't that Old One couldn't have invented Pham, Old One had to tone him down in order to use him.
Humans Through Alien Eyes: A large part of A Fire Upon the Deep is dedicated to this. Even though the human refugees ran into probably the most brilliant and scientific-minded Tines on the planet, the latter had serious problems figuring how these "alien creatures" tick.
Internet Backdraft: Invoked in A Fire Upon the Deep. On the interstellar equivalent of the Internet, humanity itself becomes a topic that causes backdraft after they get blamed for waking the Great Old One/AI.
It's All About Me: The true core of Emergents' ruling caste approach to life, as explained by Tomas Nau, but relentless, single-minded selfishness is probably the most defining trait of Vinge's villains in general.
Macross Missile Massacre: Seems to be the favorite form of combat in Beyond, from handguns that fire seemingly endless amounts of guided missiles, to swarms of jump-capable smart missiles in starship battles.
Noodle Incident: Pham Nuwen is a living, unusually bleak example of this trope, after his failed voyage to the Unthinking Depths. In addition, there are many references to his single-handedly ending a civilization-ending pogrom in a matriachal civilization (Strentmannian) with a single warship. Exactly how he accomplishes this is never explained, other then dark innuendo about atrocities committed.
Nuke 'em: How the mad governance of Tarelsk tries to deal with Qeng Ho fleet. They fails, but kills billions in process.
In A Fire Upon the Deep, there is a race of beautiful butterfly-people with huge shining eyes. They're genocidal fascists.
In A Deepness in the Sky, this is how humans look to the Giant Spiders, and they think it's unspeakably cute. The humans resemble baby Spiders, who only have two eyes. When they mature, most of their carapace becomes one large visual sensor. Even very hard-bitten, cynical Spiders were hard-pressed to resist that effect.
Ragnarok Proofing: The Spiders have to learn some of this to progress their civilization on a homeworld orbiting the On-Off star.
In A Deepness in the Sky, the effects of relativity, advanced medicine and prosthetics allows people to live hundreds or thousands of years. Pham Nuwen, constantly travelling, is possibly the oldest of the Qeng Ho, living hundreds of years from his perspective and much, much longer from most other reference frames. That, and he shows up in A Fire Upon the Deep.
A Fire Upon the Deep plays this straight with humans and many species of aliens (in fact, failure to uphold this trope on a low-tech world becomes a major plot point in the sequel), but inverts with Powers, which rarely exist for more than ten years, before losing interest in maintaining contact or changing irrecognizably.
The Hive Mind nature of the Tines means that an individual can incorporate new members as old ones die off, maintaining a continuous consciousness for many times the lifespan of an individual. Although it's not given how long a member would live, Woodcarver is over 600 years old and has seen glaciers advance and retreat over his/her lifetime. It eventually extracts a terrible price, though, as the only way to maintain one's identity after enough years is inbreeding within one's own members.
Renaissance Man: Woodcarver excels in several form of fine arts and basically invented the scientific approach, revolutionizing much of Tines' culture. On top of that he/she is a competent politician and military leader, and apparently was a Bad Ass warrior in his/her younger days. Pham Nuwen is a legendary trader, space navigator and politician, is very good at Slow Zone-level programming, and is as Bad Ass as they come, particularly when not undermined by advanced age.
Rock Beats Laser: Massively averted in A Fire Upon the Deep, where one civilian with a high-tech sidearm nearly wipes out a whole regiment of troops with medieval weapons and is only killed when natives use a primitive flamethrower.
Sealed Evil in a Can: In A Fire Upon the Deep, the Blight/Straumli Perversion is a program inside a multi-billion year old archive, let loose by unwitting archaeologists.
Space Opera: A Fire Upon the Deep in particular has a large scale.
Starfish Aliens: At least one species in each book, with extensively thought-out biology and culture. Still weirder beings are hinted at in A Fire Upon the Deep. In a partial subversion of the common use of this trope, despite extreme differences in physical makeup, all encountered races can understand each other and coexist. Only hyperintelligent Powers are truly different, and even they are only hyperintelligent, not truly transcendent and ineffable.
Staying Alive: It is unclear whether The Blight retained some self-awareness, even after being submerged into the Slow Zone, or just cooked up complicated programs for its fleet right before that, but said fleet is certainly alive and still intending to nuke the Countermeasure, alongside with the Tines' world, as soon as it gets there. Which might be far sooner than anyone's worst predictions.
The Slow Path: In A Deepness in the Sky, Thomas Nau spends no time in hibernation, so he ages faster than everyone else.
Tap on the Head: Completely averted in The Children of the Sky. The blow that knocks out Ravna is treated completely realistically, with various debilitating aftereffects until she gets advanced medical treatment.
Translation Convention: The spider sections of A Deepness in the Sky are written by human researchers, using this.
Troll: Flenser-Tyrathect apparently channels his residual sadistic impulses by getting a rise out of people. He picks underlings with similar inclinations too.
Too Dumb to Live: Scriber. He dodges this trope at the very beginning, thanks to sheer luck, but it catches up with him the next time he tries to be useful. Played for tragedy, instead of humor particularly as without his well-intentioned but poorly-thought-out actions all the good guys would have been ultimately doomed. Either time.
The Virus: The Blight. It can overtake whole civilizations at lightning speed, by infecting and assimilating their computer systems. It also can overtake living beings and turn them into its meat puppets. Normally, this takes High Beyond technology, but in the Low Beyond, it custom-created a race billions of years ago that can be instantly subverted at any distance - the Skroderiders.
Zero-G Spot: The problem of obtaining leverage during zero-g sex is mentioned in A Deepness In The Sky; also, one of the protagonists in A Fire Upon The Deep thinks that zero-g sex isn't what it's cracked up to be (again largely due to the difficulties of obtaining leverage safely).