Google TV is a sort of IPTV/universal interface hybrid. As well as providing a massive amount of online content for your TV, Google TV combines your cable STB, DVD player, Xbox, TiVo, sound system and just about anything else you have plugged in to your TV. Bringing all of your media forms together and splicing them with the internet gives you a luxuriously hassle-free way to search for entertainment. If you're after a specific movie just put the title in to the search bar and it will scan everything in seconds. You'll get an easy menu of results from your recorded programs, movies saved on your computer, movies available online, movies available on any internet subscriptions (such as Apple TV, Netflix or Zune), YouTube results, Podcast results etc. It's really easy to spot the result you're after as well. You won't be intimidated by a hoard of useless search results crowding your screen as some other IPTV services are wont to do.
The term Internet Protocol Television (IPTV) covers a vast array of products and services but for a simple definition, IPTV is basically any form of video or radio media format that can be streamed across the internet to you on an internet enabled device. More recently IPTV has become more recognised as a paid service, coming in the form of either a one-off payment or via subscription.