If you want a good overview of what kind of objects and services make up the Internet of Things, have a look at the list of Supported Things at The Thing System. The trouble with the Internet of Things is, invariably, the amount of different protocols, platforms, power cables etc. The Things often have a technical complexity we're not used to anymore.
The Thing System is a set of software components and network protocols that connects to Things in your home, whether those things are media players such as the Sonos or the Apple TV, your Nest thermostat, or your Philips Hue lightbulbs. The protocols used are Wi-Fi, USB or Bluetooth Low Energy (BLE). The Thing System's steward software will find them and bring them together so they can talk to one another and perform "magic".