NET
Instead of linking to a dispersed bunch of independent sites that you travel to as URL addresses, the Net of 2020 is basically like a giant AOL or Compuserve, with REALLY GREAT GRAPHICS. Netrunners are basically going to one or two enormous walled gardens that are defined as Net Zones (like Atlantis or Pacifica, for example). In 2013, the links to these huge zones was moderated by the use of "interfaces"--essentially preloaded data packs that acted much like the downloading patches of large MMOs during the 1980s. By the 2020, the Ihara/Grubb equations created a shared universe that served anyone logging into a Zone and didn't require a preloaded interface program because of the now superior bandwidth speeds.
I'm going to have to do a deeper cut of all this one day, but suffice it to say that I worked this all out a bunch of years back when I still worked at Microsoft. Its a big ass theoretical paper with diagrams and everything.
The all-encompassing world wide web of things, connecting anything from toasters to Cyberware to corporate Data Fortresses. The NET functions via hard lines, radio links, cell towers and any other sort of transmitters that can connect devices seamlessly.
The NET is rendered in 3D, with the modem (terminal, cyberdeck etc.) determining how the interface is displayed, from rudimentary shapes and icons to a full-blown simulation. However, the representation itself, while it adapts to the user's hardware, stays the same: a Data Fortress themed after a dragon's lair will appear like that to everybody.
The NET is a virtual space infinite in area, but limited in scope, since it has only been colonized by humans. The navigability of the NET is given by the Ihara-Grubb Transformation Algorithms, created by Rache Bartmoss, allowing users to see Data Fortress in actual distances - if a shop is three blocks away from you, its Data Fortress will also seem to be in cyberspace at about the same distance. Unstable connections or interference render as mountains, earthquakes, thick rain or fog.
Data Fortresses are the computer systems on the NET which can be accessed by anyone with an interface plug. Navigating the NET quickly and efficiently requires a cyberdeck, which gives its user an edge in Netrunning, rather than accessing via terminal.
While AIs do exist, they are restrained and controlled by their owners, usually corporate giants like Arasaka, EBM, IEC etc. It is presupposed that rogue AGIs wander across the NET, but most stay just as rumors or stories to scare off Netrunners.
In Night City, the NCPD's NETSEC is one of the most proficient ombudsmen of the NET, rivaling even NetWatch.