"Now Playing" metadata on new MP3

[vjn]

I've recoded a club meeting on my voice recorder, converted the MP3 to a wav file for editing and converted back to MP3. Now I am using VLC Media Player to insert the ID3 tags because I can write to the copyright field.

I am puzzled about the "Now Playing" field. What kind of information would I put there and when would that be displayed?
Thank you.

[Rémi Denis-Courmont]

Now Playing should describe the currently playing opus, in streams that carry multiple different opera consecutively (such as Internet "radio" channels).