When Apple first began to sell computers, its primary OS was called the MacOS and in Apple's FAQs section, which seeks to answer questions about its Earth Day campaign, the tech giant named only the MacOS, and its current OSX was not mentioned anywhere. Either this was a typo or Apple is soon going to be renaming its desktop operating system, 9to5Mac points out.
The page has been edited and calls the desktop OS OSX, but an archive page can still be accessed. While answering product greenhouse gas lifecycles, Apple lists MacOS along with the rest of its operating systems, viz., tvOS, iOS and watchOS.
As one can see, renaming the desktop OS would add uniformity to Apple's software product line, something Apple always has had a penchant for. It also bolsters rumours that pointed towards a name change when Brazilian Apple blog MacMagazine found the name hidden inside OSX's System folder.
But why refer to it with a capital 'M'? One might wonder, seeing that the rest of the OSs are stylised with a lower case alphabet. 9to5Mac believes it could be because Mac, short for Macintosh, is a proper noun while tv, watch are all common nouns. It might seem like a stretch, but it could also be true. It could also have been typed out that way because that's how the MacOS has been stylised historically.
We will probably have to wait till Apple's next World Wide Developers Conference (WWDC), where Apple is possibly expected to introduce OSX El Capitan's successor, to find out whether the change is actually going to happen.
And in case you're wondering what the 'i' in iOS stands for, it has its origins in 'internet'. Fastcode Design says that the 'i' in the original iMac stood for its ability to connect to the internet and About.com adds that the branding caught on so well that it became a part of Apple's offering. Today I Learned (TIL).