system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: If movies and shows on your DVR aren't illegal, why are they on your computer?

You have a cable subscription and you record a show/movie onto your DVR. If you were to torrent that same show/movie on your computer it becomes illegal. What is the difference?

edit: You receive your cable TV and internet from the same provider.
gpt
Consider the source.  Your cable company has a deal with the content provider.  They pay X amount of money and the creator of the show/movie agrees to let them stream the content to your TV so you can watch it or save it to your box for later.

There are websites like that, too.  Netflix is doing the same thing (though minus the "save for later" part).

But when you torrent a file, you're getting it from a source that has no such deal with the creator of the content.  They're distributing it illegally and it's not benefiting the creator at all.  That's why it's illegal.