I was not familiar with the name for this phenomenon, though it seems to be well established nomenclature. In the publishing business we tend to refer to it as Cap & lc, as opposed to Init Cap & lc (which it seems is called rather boringly Sentence case in this brave new world). Nor did I realize that Title Case is Apple’s house style, while Sentence case is Google’s. John Saito clarifies it all at Medium in a piece called Making a case for letter case.

The website TitleCase will take any text you care to enter into it and show you how it should look as 1. Title Case, 2. AP Style Title Case, 3. UPPERCASE, 4. lowercase, 5. Start Case, 6. camelCase, 7. PascalCase, or 8. snake_case. Seems you don’t need to be shown Sentence case — of course, you may want to argue that you don’t really need to be shown any of them. I guess the app is there because it can be done: I’m not sure why I’d ever find it useful! Maybe it’s a tool essential for those robots who are banging out reports on Olympic events right now. If you’ve got this far you may want to know what the difference between camel case and Pascal case is. Quora.com provides the answer to this vital question, though I couldn’t bear to read it.

This whole new area is full of mystery. One may be this wrenching of the meaning of “case” from its familiar typecase origins.