What exactly are these things and what's the jailbreak do? Are they not designed to browse the net or something and the jailbreak lets you do it?
the amazon fire stick is a small dongle that plugs into the HDMI input of your TV and allows you to watch different streaming services like amazon video, netflix, hulu and channels that have streaming services like ESPN and HBO. of course it requires a subscription to each of those services. it's like apple tv, google chromecast, or roku, if you're familiar with those devices. most of the newer blu-ray players also have the ability to stream from a lot of these services.
the stick runs on android and has wi-fi, so you can essentially install anything on it that runs on your android phone, including Kodi. people refer to this as "jailbreaking", although it's not quite the same as jailbreaking an iphone. basically when they say "jailbreaking", they just mean installing programs that aren't officially approved in amazon's app store.
Tell me more about this. How does it know which games to stream?
Kodi is a media front-end that started off as a program called XBMC (xbox media center) which was developed for people to manage and serve their media files (movies, music, pictures) to a display device or to other computers on your home network.
various third parties have developed addons which allow you to access media streams from various sources. sportsdevil, which kontra mentioned, is one of the addons for streaming live sports. there are others:
Best 2016 NFL Kodi Live Streams (National Football League)
just to note, since no one else did (maybe because it's obvious), but these streaming sources are illegal. kodi doesn't support any of these addons and bans discussion of them on their forums:
Official:Forum rules/Banned add-ons - Official Kodi Wiki
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