Storing Sprite Kit Level Data

There is a project I am working on in which a set of targets appear onto the screen. The targets should appear a certain amount at the same time, and with a certain delay in between each appearance. My question is how I would correctly store the level data for this game. I was considering using a csv file to store the level data (target type, location, delay, etc.), but I'm wondering if there is a better way to do it. I had also considered making a level object to store level information, but I'm not sure. Apple says to use 'Archives of sprite nodes', but I can't seem to find out what that means. Any thoughts?