In QA Engineering what's testing "a case grid"

Sorry for not being so thoroughly but I have an Interview in a couple of days. Will be for a QA Engineer in a POS Company.

And the only "hint" that I got is that There's going to be a test, a case grid that I have to test. I've been in testing for a while now, but never heard of this.

Does anyone knows anything about it?

Thanks!