What system types is this thermostat compatible with, and what won't it work with?

This thermostat works with common 24-volt systems including forced air, hydronic, heat pump, oil, gas, and electric systems. It will not work with millivolt systems such as a gas fireplace, or with 120/240 volt systems such as baseboard electric heat. (Page 4)

From the official Honeywell RTH6580WF Wi-Fi Smart Thermostat manual, page 4

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