autoplay currently shows the following description
Automatically running programs from inserted discs, USB flash drives, etc.
This suggests that something physical has to start. However, auto play could be for other reasons.
This question was tagged with autoplay. On a Mac, how do I get rid of Disable HTML5 Autoplay plugin?
Obviously the trigger for auto-play is when the web page loads (or similar).
Due to the current description of autoplay, I removed it from the post.
As I don't like editing the tags without verification first, can you please vote on one of my 2 answers below (or post your own).