In retail, an SKU is a unique identifier. In the context of , we propose that users and collectors began tagging unsold digital goods, legacy file types ( .aid , .m4p ), and refurbished iPods with a fictional "iTunes Stock Keeping Unit." This allowed second-hand markets (eBay, Craigslist, Etsy) to categorize items that were neither modern Apple products nor obsolete trash.
: A more recent research paper (CSCW 2019) that discusses redefining units of interaction in digital research tools, moving beyond the "iTunes model" for document management. joelchan.me "Papers" App (iTunes-style Document Manager) There is a popular application actually called itunesku