How do spotify playlists work?

Factual Questions
1

So I have a couple of playlists I want to upload to spotify. The procedure seems to be

  1. Make a playlist in iTunes and use a program to convert to a spotify playlist.
  3. Profit

Do the songs get uploaded as well?
If not, what happens if a song is not in their library or violates RIAA’s interpretation of copyright law?
Can anyone add to a playlist or is it optional?

2

I’m no expert on iTunes, but unless the playlists you have are really long I would advice you to skip a step and make the playlists directly in spotify. Just click on “new playlist” and search for the songs and click “add to playlist”.

You can choose whether to make them public (visible to others) and/or collaborative (others can add to them) if you want to.