Yup same here. My parents had both sick days and vacation days. Sick days were PTO you could use the day of, and vacation days needed to be scheduled ahead of time.

Everywhere I've worked that has either had no paid time off at all, or it has just been one bucket and you had to schedule it no less than 48hrs in advance, or they would automatically deny it. As in it would never reach a human being, the timekeeping system would just reject it outright.

I'm hearing more and more of the PTO term lately as well but still see some companies that categorize sick days in a separate non-carryover bucket. Vacation days may be a more generational thing that is phasing out I still hear that term (it's in some of the posts here), and then see it in articles such as this one so it's still out there conveying the wrong idea.