Wireless Smart Home Devices need 3 components in order to work:
1. The smart device itself, like a hue light bulb or smart light switch.
2. A Hub, like a Samsung SmartThings Hub or a Philips Hue Hub. These Hub typically communicate with the smart device via z-wave or zigbee wireless standards. Since these Hubs and smart devices use these wireless standards, they don't need to be made by the same manufacture in order to work together... for example you can use Philips Hue bulbs with a Samsung SmartThings hub. Hubs usually support more than one smart devices on one hub. These Hubs also have either an Ethernet port or Wi-Fi or both to connect to your home network.
3. A control device, like a Smartphone, Tablet, or Google Home. The control device connects to the Hub over your home network. Some Hubs offer services where you can create an online account and you are able to control your smart devices over the internet. On phones and tablets you typically access and control the Hub through an app you download on your device. Hubs usually support multiple control devices connected to one hub, so you can have one Hub which you control through both your phone and Google Home.