The suffix _source indicates this is the original, high-resolution version of the video before it was processed into different bitrates for streaming.

These strings are randomly generated unique IDs. Without the original post link, the specific subject matter (e.g., a meme, a news clip, or a tutorial) cannot be determined just by looking at the text.

While the filename itself doesn't contain a descriptive title, here is what it tells us: It originates from Reddit's media servers.

If you found this in your browser cache or a download folder, it is likely a video you recently viewed on a community.

The filename is a specific identifier typically used by Reddit for videos uploaded directly to its platform (hosted on v.redd.it ).