Neuromancer was the first offering from the man who coined the term cyberspace. Before the net existed, he wrote about it, not the details of webpages and search engines, but the vast interconnecting structure of data that is the world of information today.
Gibson claims that at the time of writing, he didn't even own a computer.
First impressions are chaotic, it takes the first chapter or so to being understanding the where and what of the Sprawl. Jargon and short, sharp description create a jarring effect that sets the mood for the book. Yet the jargon is easily understood, even more intuitive today than when it was written, and while it helps set the scene, it doesn't confuse or alienate the reader.
To my mind the world of the sprawl will always be linked to the atmosphere from Bladerunner, the combination of high tech and poverty, the flash of neon and the dirt, where even, or perhaps especially, the tech-savvy are the criminals.
The main character is Case, a minor criminal who makes his living being a middle-man, running fast deals that will culminate in his death. He doesn't really want to live, he used to be a console cowboy, an elite hacker in cyberspace, punching into a virtual reality interface straight into the world of data. But his ability is gone, destroyed by a virus after he betrayed his last employer.
Into the middle of his business steps Molly, a mercenary with useful upgrades, including retractable razor blades under her nails and mirrored lenses inset over her eyes. She works for Armitage, a cold and mysterious man who is assembling a team for an unknown purpose, and he provides the tech that fixes Case, enabling him to be their cowboy.
Case and Molly form an alliance, trying to discover the real identity of Armitage and who he works for, and they gain some information after they do a hit on the SenseNet library. Stacked with all the entertainment data of the entertainment network, they take only one thing. The stored personality file of Case's old teacher, the Dixie Flatline.
The team is complete when they pick up Peter Riviera, an entertainer who projects holograms, but who is completely mad. The situation becomes clear when they go offworld to the Tessier-Ashpool Orbital Freeside. Riviera is to attract the attention of 3Jane, one of the Tessier-Ashpools who live in the high security spindle at one end of the orbital. He is to get himself invited in, and then find a way to let in Molly while Case attacks the data structure.
Case is having increasing contact with their true employer, Wintermute, one of the two Tessier-Ashpool AIs, who wants to break free from the restrictions set on all AIs by the Turing Registry. The other AI, Neuromancer, is trying to stop them from achieving this.
During the operation, Case has several encounters in cyberspace with Wintermute and Neuromancer, sometimes having trouble distinguishing the two. After completing the run, they find that they have money and all trace of their actions has been destroyed, while Wintermute and Neuromancer have been merged into one being.
The real power of this book is in the environment, the description of fine detail and the use of simile to relate new concepts to familiar ones. Surprisingly Neuromancer has not become dated, despite being over twenty years old, and predating IT as we know it, it still rings true as a near-future novel. Most scifi that deals so heavily in the near future and the use of new tech shows it's age within a couple of years of publication, but Neuromancer is a book you can reasonably give to any teenager today and expect them to find it just as interesting and fresh as it was when it was released.
In my opinion it has been matched by only two or three cyberpunk novels since, and still defines the genre for me.