Reference
Glossary
The words that come up again and again across the guides, defined without jargon.
A
- Actigraphy
- The measurement of movement over time, usually with an accelerometer, to infer activity, rest and sleep patterns.
- Actuator
- A device that turns an electrical signal into a physical action — a motor, relay, valve or lock. Actuators are the "output" half of an intelligent environment; sensors are the "input".
- Ambient assisted living (AAL)
- The use of sensing and automation to help people — often older adults — live independently and safely at home, for example through fall detection or medication reminders.
- Ambient intelligence (AmI)
- A vision of environments that are sensitive and responsive to the people in them, working quietly in the background rather than demanding attention.
B
- BACnet
- A communication protocol widely used in building automation so that equipment from different manufacturers — HVAC, lighting, access control — can interoperate.
- Building management system (BMS)
- The central platform that monitors and controls a building’s services, such as heating, ventilation, lighting and security, from a single interface.
C
- Context awareness
- A system’s ability to use information about its situation — location, time, activity, who is present — to adapt its behaviour without explicit instructions.
D
- Digital twin
- A continuously updated virtual model of a physical asset — a machine, building or city — fed by live sensor data and used for monitoring, simulation and planning.
E
- Edge computing
- Processing data on or near the device that produced it, rather than sending everything to the cloud, to cut latency, bandwidth and privacy exposure.
G
- Gateway
- A device that bridges local sensor networks (Zigbee, Z-Wave, Thread, BLE) to the internet or to a home hub, translating between protocols.
H
- Home automation
- The control and scheduling of household devices — lighting, climate, locks, blinds — through rules, sensors or voice, with or without cloud services.
- Hub
- A central controller that coordinates smart-home devices, runs automations locally, and often speaks several wireless protocols at once.
I
- Internet of Things (IoT)
- The extension of network connectivity to everyday physical objects so they can collect data, be monitored, and be controlled remotely.
K
- KNX
- An open standard for building control, common in Europe, that connects lighting, blinds, HVAC and more over a shared bus.
L
- Latency
- The delay between a cause and its effect in a system — for example, the lag between pressing a switch and a light responding. Low latency matters for anything that feels "instant".
- LoRaWAN
- A low-power, long-range wireless protocol suited to battery sensors that send small amounts of data over distances of kilometres.
M
- Matter
- An application-layer smart-home standard designed to let devices from different brands work together over IP, regardless of the underlying radio.
- MQTT
- A lightweight publish/subscribe messaging protocol widely used to move sensor readings and commands between devices, gateways and servers.
O
- Occupancy sensing
- Detecting whether a space is in use, and sometimes how many people are present, to drive lighting, climate and security. See also presence detection.
P
- Pervasive / ubiquitous computing
- The idea, articulated by Mark Weiser, that computing would spread into everyday objects and surroundings until it became effectively invisible.
- PIR sensor
- A passive infrared sensor that detects motion by sensing changes in infrared heat, the most common trigger for automatic lighting and alarms.
- Presence detection
- Determining that a person is present even when still — increasingly done with millimetre-wave radar, which sees breathing-scale motion that PIR misses.
S
- Sensor fusion
- Combining data from several sensors to produce a more accurate or complete picture than any one sensor could give alone.
- Smart building
- A building that uses connected sensing and automation to improve comfort, safety and energy performance, and to run its services more efficiently.
- Smart city
- An urban area that applies sensing, data and automation across transport, utilities and public services, with the aim of running the city better.
- Smart home
- A residence where devices for lighting, climate, security and entertainment can be monitored and controlled remotely or automatically.
T
- Telecare
- Remote support for people at home through connected alarms and sensors that can summon help, often used in ambient assisted living.
- Thread
- A low-power, IP-based mesh networking protocol for smart-home devices, used as one of the transports beneath Matter.
Z
- Z-Wave
- A proprietary low-power mesh protocol for smart-home devices, known for interoperability certification and a sub-gigahertz radio band.
- Zigbee
- A long-established low-power mesh protocol for home and building automation, using its own application layer rather than IP.