This was the year of clap backs, tea, and receipts. The messier the situation, the longer the list of receipts. And 2016 was a really messy year.For those of you wondering, WTF are receipts?, here's a crash course. Receipts are basically evidence or proof that someone did something. The expression derives from the conventional meaning of a receipt that shows proof of purchase, but in this case, it's showing proof of shade. Its origin is disputed, but many credit the unforgettable Whitney Houston interview with Diane Sawyer, in whichSawyer reads a headline to Houston alleging that the singer spent $730,000 on drugs in a year. Houston replies, "Show me the receipts." And thus, receipts were born.The meaning of the word has evolved through the years, but now it's most often used in reference to a pop culture event, specifically one in which one celebrity backs up a complaint or feud with hard evidence. Think Kim Kardashian sharing a video of Taylor Swift giving Kanye West permission to use her name in his hotly disputed song, "Famous." Kardashian had all the receipts, and she laid them out for the world to see.That might be the most iconic receipt moment of the year, but there were plenty of other golden ones. Let's open up our checkbooks and take a look.