Abbreviation for "Harvard, Yale, Princeton, or Stanford." These are the four top colleges in the US. Other schools like Penn or MIT are up there, but don't quite match the prestige.
Friend 1: "My best friend from Penn got a Rolex from his dad over dinner at graduation right in front of me. I graduated from Penn too a year ago, so I came back to my parents and asked 'Where's my Rolex?'"
Friend 2: "Haha, I bet they were like 'hmph.' But if my kids graduate from a top university, I'd probably buy them that watch. Would you?"
Friend 2: "Only if it's one above Penn, heh... Okay, maybe Penn or better."
Friend 1: "Well, that's ridiculous. You're basically saying they have to graduate from HYPS to get a Rolex... Otherwise, they'll have to buy their own watch."
Friend 1: "Fuck 'em. They can buy a Timex."