Here are some common terms and phrases utilized by Apple HomeKit and iDevices products:
Homes - The largest collection of your products containing your Rooms, Zones and Scenes.
Rooms - A group of products organized by where they live in your Home (e.g. Master Bedroom = Desk Lamp, Stereo, Alarm Clock).
Products - The name that you assign to an iDevices product, such as the Thermostat.
Zones - A collection of Rooms that you may want to control simultaneously (e.g. Upstairs = Master Bedroom and Kids’ Bedrooms).
Scenes - A set of actions taking place simultaneously with multiple products or Rooms (e.g. “Going To Bed” Scene might turn off your bedroom lights and shut your garage door).
Services - The primary function or category assigned to a product such as fans, light bulbs, garage door openers, outlets, etc.
Service Groups – Allows you to group together multiple products based on their Service Type in order to be controlled by Siri. (e.g. A Thermostat Service Group would allow you to adjust the temperature for all the iDevices Thermostats in your home, regardless of their location, but no other products).