Corporate fiscal calendars are, IMO, best thought of as essentially made up. They start and end at arbitrary-ish¹ points in the year, and thus their numbering does not always match the "calendar year" (the one you're normally familiar with).

For example, there are easy to read sites with explanations like https://www.thebalancemoney.com/how-do-i-determine-my-compan..., and less easy to read things like Form 1128.

The fiscal year is a pretty standard finance concept, so anything in that area isn't going to bother with an explainer; you're just expected to know.

From the outside looking in, it just seems nuts. If I ever found a company I'm going to do my best to get my fiscal year to == calendar, if I can. It also annoys me when companies needlessly use it internally. Mine does, I have no idea when the quarter ends anymore.

¹ish. I think the IRS has a few rules.

We're literally in fiscal year 2025. The report also calls it fiscal year 2025.

Fiscal years are about when you'll pay tax. This is Q1 of four quarters to be reported before Nvidia pays tax in 2025.

It's a fiscal year convention. Companies use the following year to reference the fiscal year because the fiscal year is named after the year in which it ends.