Quiz Entry - updated: 2026.09.18
What counts as a "cyber system", and what are the four commonly distinguished kinds?
Everything where digital technology processes information — conventionally split into IT, OT, IoT and cloud.
* One term, four very different security problems — and most estates contain all four at once. *
The wide term matters because a security architecture that only knows about office computers will be blind to the parts of the estate that can hurt people or stop production.
| Kind | What it is | Typical examples |
|---|---|---|
| IT — information technology | The systems, networks and computers of the classic business-office, home-office and internet world | Notebooks, file and mail servers, ERP, intranet, web shop |
| OT — operational technology (Prozessleittechnik, process control) | The means and procedures for controlling, regulating and safeguarding process plants, production lines and industrial installations | PLCs, SCADA, a bottling line's controller, a milking robot |
| IoT — internet of things | Small, often minimal devices deployed en masse into the public space of the internet; they receive signals, measure, control, regulate, and collect, process and forward information | Sensors, smart meters, trackers, connected cameras |
| Cloud | Services consumed from a provider rather than run in-house | SaaS office suites, cloud storage, a hosted web shop, PaaS databases |
Two distinctions are worth holding onto:
- IT protects data; OT protects a physical process. That inverts the usual priorities — in IT the classic ranking is confidentiality, integrity, availability; in OT, availability and safety come first, because a "protective" measure that stops the plant is the incident.
- IoT is defined by scale and minimalism, not by cleverness. A device too small for an agent, too cheap to patch, and deployed ten thousand times is a different security problem from one well-tended server.
Go deeper:
Wikipedia — Operational technology — how OT grew from isolated proprietary kit into something that now depends on IT infrastructure.- Wikipedia — Internet of things — the scale side of the problem: why mass-deployed minimal devices are their own category.