an object is like a row of a spreadsheet, the header row of a spreadsheet is like a class or constructor.
if i want a playlist, it would be nice to be able to sort by year, title, artist, etc.
in js, each playlist item would be an object, and the list itself is an array (if you needed one). arrays are just objects that use 1, 2, and 3 instead of a, b, and c.
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