Assuming you're familiar with basic programming concepts, it is practically speaking just the abstract definition of a way to ingest and pass around data in an unfamiliar context. Promises are a great example (packaging data for async processing), or the "Optional" wrapper on JVM return signatures (Passing around an object for possible-null handlers). Both those implementations fail on some purity grounds, but they're good for understanding the gist of your question, i.e. "the point" of one. (Even though I'm 73% sure some Haskell-ite is going to respond to me with an _ACTUALLY..._)