system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5:why does tv signal manage to have no buffer when you watch tv, while internet videos buffer a lot ?

As the title, how come when you watch tv there is no buffer on the shows while on the internet it can buffer a lot, i mean both are radio signals right ?
gpt
TV, whether over the air or over cable TV, is "broadcasting" one thing to everyone who can possibly receive it.  If you've got an antenna and are tuned in, you will see whatever is going on right at that moment.  There's no buffering, because there's no before, no after: you can only receive what's being sent at that exact moment.   If you want to rewind or fast-forward, you need to have some recording device like a tape recorder or DVR -- or, if you're having trouble receiving the signal, you'll get either a degraded signal or none at all.  In a sense, this is *worse* than buffering, because if there's an interruption in the signal, what was missed is simply lost forever.  But, since the same thing goes out to everyone, it has an uninterrupted, constant stream of video that anyone with the right equipment can tap into, but only to see what's on right at that moment.

The internet, however, everyone has to have their own, private, separate 'path' for the video to get to them -- millions of TV channels trying to use the same internet at once.  Due to internet speeds and how internet hardware works, sometimes one of those private 'paths' has to stop and wait for someone else's data to use the same wire.  This is the nature of the internet; it's fast, but there's no guarantee anyone's data will get there when it is expected.

So, online video and audio use *buffering*, which essentially starts recording the streaming data off the internet -- which is stopping and starting and pausing slightly and suddenly is faster than regular video speed but then slows back down -- and then is playing it back at 'live' speed for you.     Even if you're watching the same thing on your computer as someone sitting next to you, you're not *really* watching the same thing -- you each have your own, dedicated broadcast station sending you your data, trying to share the same wire, which means two copies of the same video are on the same wire at the same time.  As more and more different video connections try to use the same wires, it slows down even more, causing buffering to try and save ahead even further than before.