It's basically a box that allows you to stream internet content through your television set. Many new TVs are being built with internet connectivity, making a Roku device redundant.

There is a lot of "free" movie/tv/video content available online. Most can be found by spending a few minutes on goggle. I found quite a bit when our television died, and more later because the new one does have internet capability.

Internet Archive: Digital Library of Free Books, Movies, Music ...
Internet Archive is a non-profit digital library offering free universal access to books, movies & music, as well as 390 billion archived web pages.

Crackle - Watch Free Movies Online – Full-Length Streaming Movies

Free Full Movies - Complete - YouTube
I spent a couple of weekends watching full commercial-free episodes of The Adventures of Superman series from the '50s with George Reeves. There are a lot more nuggets hidden in YouTube than one might think.

MoviesFoundOnline.com - Watch free streaming movies, documentaries, cartoons and TV-shows online.

Popcornflix: Watch Free Movies Online

Open Culture - The best free cultural & educational media on the web

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Some have commercials - some don't.

There are also (too many to list) sites for watching TV channels from around the world, including broadcast, webcast, and cable.

free online tv channels from around the world

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