what is the second system mentioned?
It is a series of proprietary graphical operating systems developed and marketed by Apple Inc
MacOS
macOS (; previously Mac OS X and later OS X) is a series of proprietary graphical operating systems developed and marketed by Apple Inc
league of legends how many players per team Five what is this game about? Multiplayer online battle arena video game where can you play this game? Microsoft Windows and macOS
wiki:25674251
MacOS [SEP] Introduction
The "X" in Mac OS X and OS X is the Roman numeral for the number 10 and is pronounced as such. The X was a prominent part of the operating system's brand identity and marketing in its early years, but gradually receded in prominence since the release of Snow Leopard in 2009. In 2020, Apple incremented the major version number to 11 in macOS Big Sur, although it retains the same base as the previous versions of macOS. UNIX 03 certification was achieved for the Intel version of Mac OS X 10.5 Leopard and all releases from Mac OS X 10.6 Snow Leopard up to the current version also have UNIX 03 certification.