It's a hard-sci-fi story about how various societies, human and alien, attempt to assert control & hegemony over centuries of time (in many ways thinking of this as a distributed systems and code documentation problem!), and how critical and impactful the role of language translation is in helping people to understand foreign ways of thinking.
At the novel's core is a question very akin to that of philosophical antipositivism [1]: is it possible (or optimal for your society's stability) to appreciate and emphasize with people wholly different from yourselves, without interpreting their thoughts and cultures in language and description that's familiar to yourselves... even if in so doing this becomes more art than science? Is creative translation ethical if it establishes power dynamics that would not be there otherwise? There's a mind-blowing meta-narrative to this as well when you think about how the reader should interpret the book with that question in mind, though to say anything more would delve into spoilers. And lest you think it's just philosophical deepness, it's also an action-packed page-turner with memorable characters despite its huge temporal scope.
While technically it's a prequel to A Fire Upon The Deep, it works entirely standalone, and I would argue that Deepness is best read first without knowing character details from its publication-time predecessor Fire. Content warnings for mind control and assault (though they're handled thoughtfully IMO). With Asimov's Foundation being adapted for TV (also recommend, if for the visuals alone), if you want even more sci-fi that speaks to societal rise and decline, and the lengths to which people will manipulate others in the name of control and survival, this is a must-read.
[0] https://www.amazon.com/Deepness-Sky-Zones-Thought/dp/0812536... [1] https://en.wikipedia.org/wiki/Antipositivism