Every term on this page gets used somewhere on this site. Every one of them got the “what does that even mean?” treatment from us at some point. This is our working translation key, in plain English.
Use Ctrl+F (or Cmd+F on a Mac) to jump to a term.
A
Add-on. A small optional piece of software that installs inside Home Assistant to extend what it can do. Examples: Mosquitto (an MQTT broker), Frigate (camera object detection), File Editor (edits config files from the browser). You install add-ons from Settings → Add-ons. They’re not the same as integrations (below).
Automation. A rule that says “when X happens, do Y.” The core feature of Home Assistant. A single automation can have multiple triggers, conditions, and actions chained together. See our first automations guide.
B
Binary sensor. A sensor that’s either on or off. Motion sensors, door/window sensors, and smoke detectors are binary sensors. Either someone’s in the room or they aren’t.
Blueprint. A reusable automation template someone else made. You import the blueprint, fill in a few fields (which light, which sensor), and get a working automation. Community blueprints live at home-assistant.io/get-blueprints.
C
Companion app. The official free Home Assistant app for iOS and Android. Gives you the dashboard in your pocket, push notifications from automations, and turns your phone into a sensor (location, battery, Wi-Fi network).
Condition. The “only if” part of an automation. “Turn on the porch light at sunset (trigger), only if it’s a weekday (condition).”
Coordinator. The USB stick that lets Home Assistant talk to Zigbee or Z-Wave devices. Each protocol needs its own coordinator. The SkyConnect is a common Zigbee one; the Zooz ZST10 is a common Z-Wave one.
D
Dashboard. The screen you look at when you open Home Assistant. You build it from cards (tile, weather, entity, area). See our dashboard guide.
Developer mode / developer tools. A section in HA (Settings menu) that shows you every entity’s current state, lets you fire test events, and lets you inspect templates. Useful for debugging, ignore on day one.
Device. The physical thing. A Hue bulb, a motion sensor, a thermostat. A device is usually made up of multiple entities.
E
Entity. A single controllable or readable state in Home Assistant. One device often has many entities. A smart plug device has an on/off entity, a power-usage entity, and sometimes a temperature-of-the-plug entity. You mostly interact with entities, not devices.
ESPHome. Free firmware you install on cheap microcontroller boards (like the ESP32) to turn them into custom sensors or controls that integrate with Home Assistant locally. Powerful but advanced. Skip on day one.
F
Frigate. A free object-detection system that runs inside Home Assistant as an add-on. Watches your security cameras and notifies you about “person,” “package,” or “vehicle” instead of just “motion.” See our Ring replacement guide.
H
HACS (Home Assistant Community Store). An unofficial catalog of community-built integrations, cards, and themes. You install it once, then you can browse and install community extensions from inside HA. Great stuff in there. Also the door into the more technical half of HA. Don’t install on day one.
Home Assistant Core. The “bare” version of Home Assistant that runs as a Python app. More flexible but harder to manage. Most beginners should use Home Assistant OS instead.
Home Assistant Green. The official plug-and-play appliance for running Home Assistant. $99, comes with HA pre-installed. See the hardware guide.
Home Assistant OS. The recommended full operating system for running Home Assistant. Ships as a single image you flash to a Raspberry Pi, HA Green, or other device. Includes add-on support and automatic updates.
Home Assistant Voice Preview Edition. The official Home Assistant voice assistant. An early product that’s getting better fast. An alternative to Alexa or Google Home if you want voice control that stays local.
I
Integration. A connector that teaches Home Assistant how to talk to a specific brand or service. Philips Hue is an integration. National Weather Service is an integration. Google Cast is an integration. You add them from Settings → Devices & Services. See our integrations shortlist.
L
Local / local control. The device and Home Assistant communicate directly on your home network, without involving any outside servers. Faster, more private, and works when your internet goes down. Contrast with cloud-based control.
Lovelace. The old name for Home Assistant dashboards. Still shows up in docs. Same thing.
M
Matter. A newer smart home protocol designed to make devices work across ecosystems (Apple Home, Google, Alexa, Home Assistant). Runs over Wi-Fi or Thread. Promising, still maturing. See our protocols guide.
Mosquitto. A popular free MQTT broker available as a Home Assistant add-on. Required by some add-ons like Frigate and Zigbee2MQTT.
MQTT. A lightweight messaging protocol that many smart-home tools use to talk to each other. You don’t need to understand it to use Home Assistant, but you’ll see it referenced. Think of it as a shared chat room for devices.
N
Nabu Casa (Home Assistant Cloud). The $6.50/month subscription from the company that funds Home Assistant. Gets you remote access, Alexa and Google voice integration, and better TTS voices. Optional. See our Nabu Casa breakdown.
P
Piper. A free, open-source text-to-speech engine that runs locally inside Home Assistant. The default voice for Home Assistant Voice, and a solid free alternative to cloud TTS.
Presence detection. How Home Assistant knows who’s home. Usually runs through the Companion app’s location tracking, sometimes augmented with router-based detection or Bluetooth beacons.
R
Raspberry Pi. A small, cheap single-board computer commonly used to run Home Assistant. The Pi 4 and Pi 5 both work well. See the hardware guide.
Restore / snapshot / backup. Home Assistant can take full backups of its config and data. Under Settings → System → Backups. Take one before any big change, especially before updating.
RTSP. The protocol used by most IP security cameras to stream video. You’ll see RTSP URLs when you set up cameras in Frigate or the generic camera integration. Looks like rtsp://username:password@192.168.1.50/stream.
S
Scene. A saved state across multiple devices. “Movie night” might be: living room lights at 20%, TV backlight on, thermostat at 70. Activate the scene and everything snaps to that state. Great for one-tap mode switches.
Script. A named list of actions you can run on demand or from an automation. “Good night script”: turn off lights, lock door, set thermostat to 65. See our first automations.
Sections. The modern dashboard layout. A grid of boxes you arrange to hold your cards. Replaces the older Masonry layout. Use this one.
Sensor. Anything that reports a value to Home Assistant. Temperature, humidity, energy use, battery level. Most devices expose at least one sensor.
SkyConnect / Home Assistant Connect ZBT-1. The official USB coordinator from Home Assistant. Supports both Zigbee and Thread. About $40. A good choice for future-proofing.
Smart home / smart device. Any device that can be controlled beyond a physical switch, usually over Wi-Fi, Zigbee, Z-Wave, or similar.
SONOFF Zigbee 3.0 USB Dongle Plus. A popular community-favorite Zigbee coordinator, around $30.
T
Tailscale. A free VPN that’s the easiest way to access Home Assistant remotely without paying for Nabu Casa. See our Nabu Casa guide.
Template. A small snippet of code that calculates a value dynamically. “Good morning, it is [current temperature] outside.” You can write templates without being a programmer, but it takes some practice.
Thread. A low-power mesh radio protocol, similar to Zigbee but built for Matter. Many Matter-over-Thread devices exist now. You need a Thread border router (built into some Apple TVs, HomePods, and the SkyConnect).
Tile card. The workhorse dashboard card. Shows one entity with an icon, name, and current state.
Trigger. The “when” of an automation. Time, sunset, motion detected, door opened, phone arrives home, a temperature crossing a threshold. An automation can have multiple triggers.
TTS (text-to-speech). What makes Home Assistant talk through your speakers. “The garage door is still open.” Uses local voices (Piper) or cloud voices (Amazon Polly, Google Cloud) via Nabu Casa.
W
Wi-Fi smart device. A smart device that connects directly to your home Wi-Fi, usually via a phone app. Easy to set up but often cloud-dependent, and Wi-Fi gets congested fast. Good for cameras and doorbells, not great for bulbs and sensors.
Y
YAML. The configuration file format Home Assistant uses for advanced setup. Looks like indented lists of keys and values. Most beginners can use the visual editors and skip YAML entirely. When you do eventually touch it, tabs are forbidden and indentation matters.
Z
Zigbee. A mature, low-power mesh protocol for smart home devices. The default we recommend for most beginners. Requires a USB coordinator. See our protocols guide.
Zigbee2MQTT. A community-built alternative to Home Assistant’s default Zigbee integration (ZHA). More flexible, more device support, slightly more setup.
ZHA (Zigbee Home Automation). The official built-in Zigbee integration. Simpler than Zigbee2MQTT and works well for most beginners.
Z-Wave. An older, reliable mesh protocol. Strong for locks and in-wall switches. Separate radio from Zigbee, so you need a Z-Wave coordinator USB stick. See our protocols guide.
Don’t see something you’re trying to decode? Let us know. We add terms as we go.
Home Assistant. Simply.