They’re essentially the same, but you only need to run one wire to them instead of two. The PoE means you don’t need to worry about getting power to the camera, which historically has been one of the more expensive parts of installation; It usually means tying into existing electrical boxes if they’re nearby, or pulling new lines if they’re not. But with PoE, everything is on that one cable.

There’s also the advantage that a networked system can be controlled remotely. Things like pan/tilt/focus/etc can be remotely controlled via Ethernet. So if you have configuration options with the camera, you don’t need to physically access it with a ladder just to make those adjustments.

As for the actual video, it’s not much different; Everything lands at a centralized hub, which then records the video or streams it to a remote server, which then records it. There are advantages and disadvantages to either, and it’s typically advised to do both. Because with a local server, once a thief gets physical access to it, they can do whatever they want with it. You were relying on that video footage, but now it’s useless because the thief took all of your hard drives. With a remote system, the big disadvantage is that it’s reliant on your internet connection. So all a potential thief has to do is cut the line going into your house.

For a truly “secure” system, the general consensus is two local servers and a remote server. Have one local server accessible, in something obvious like a server rack. Then have another redundant server somewhere else, which is more hidden and more difficult to access. And put power backups on those local servers, so they can’t simply cut the power at your breaker panel. The hope is that even if they cut your internet and/or power, and destroy the first local server, you still have the second local server. This is notably easier to do with a PoE system, due to the aforementioned lack of power runs to the cameras. Just put your network on the power backup, and the cameras will continue to function even after the power is cut. But that’s hella expensive, and would typically be reserved for enthusiasts, paranoid apocalypse preppers, and/or rich people.

Easier and cheaper to install and maintain.

Only needs a single cable that can come from any PoE switch.

CCTV is just out-dated.

Digital. Can use regular computer as recorder.