If you're looking to install or download videos for offline viewing or other purposes, consider the following:

A dedicated computer (or NAS drive) runs software that organizes your local files and streams them to client apps.

If your media has sound but no picture, you are missing a video codec. Install the K-Lite Codec Pack (Basic or Full). This instantly allows Windows Media Player or Films & TV to play modern HEVC (H.265) files, which are 50% smaller than old H.264 files at the same quality.

These platforms have slightly different rules regarding installing popular media.

For music and podcasts, "install" means "download to library."

While streaming is convenient, true enthusiasts know that to permanently install entertainment content and popular media without subscription fees or internet dependency, you need local files. This method requires more technical skill but offers the highest quality (lossless 4K Blu-ray rips).

The phrase "install entertainment content and popular media" is changing again.

Netflix allows you to "install" (download) content onto up to 100 devices per account.