Eli5: what happens on the server when one selects to watch a movie on Netflix and how the architecture allows 500k other people to watch the same movie almost concurrently?

Question

Eli5: what happens on the server when one selects to watch a movie on Netflix and how the architecture allows 500k other people to watch the same movie almost concurrently?

In: Technology

Answer 1

Across the world Netflix has thousands of cheap servers with a lot of storage whose only job is to handle downloads.

Two people don’t stream the _same_ movie file. The server lets them each download their own copy of the file _as they are watching it_.

Streaming is just watching the parts of a movie you’ve already downloaded while you’re downloading it. Buffering is when you catch up to what you’ve downloaded.