Everyone who has a computer and a broadband Internet connection can watch IPTV, but most of us don’t want to watch television on a crude laptop screen. That’s why the future of IPTV is likely to involve viewers buying set-top boxes (sometimes called STBs) that receive input from your Internet connection (either via an Ethernet cable or Wi-Fi), decode the signal, and display a picture on your high-definition, widescreen TV. STBs are effectively standalone computers programmed to do only one thing: receive packets of streamed video, decrypt them, convert them back to video files (MPEG2, MPEG4, or whatever format they were in originally), and then display them as high-quality TV pictures. Apple TV works broadly this way, using a set-top box to run simple apps on a slimmed-down operating system (tvOS), which manages the process of streaming video via the Internet.
As a simple, more compact, and much more discreet alternative to a set-top box, you can use what’s called a dongle, which looks a bit like a USB flash-memory stick, but allows secure access to Internet TV programs. The dongle plugs into an HDMI (high-speed, high-definition digital video) socket on your TV and connects via Wi-Fi to the Internet to stream TV programs, movies, and music directly. Some dongles are entirely self-sufficient: Roku and Amazon Fire work this way without any help from a computer or mobile device. Google’s Chromecast is a little bit different: generally, you get it going with your computer, tablet, or smartphone (which effectively becomes a remote control), after which it directly streams your movie or TV program from the Internet.
What’s the difference between a set-top-box and a dongle? It’s pretty much this simple: a set-top system is a bigger box that contains a faster processor with more memory, so it can give higher quality video output; that makes it better for things like high-performance gaming. Some companies, such as Amazon and Roku, offer a choice of either a simple, relatively expensive dongle or a more expensive, higher-spec set-top box.