Actually, Mac OS is Linux...
> Actually, Mac OS is Linux...
Actually, NO IT'S NOT. Emphatically not.
MacOS is based on FreeBSD Unix, not Linux. Completely different at all levels except "work-similar".
The Linux kernel was written as a "work-alike" for Unix in the early 90's, but that kernel and the BSD Unix kernel are completely different "under the hood". The system libraries of Linux and BSD are likewise completely different, even though they implement similar functionality.
Both BSD and Linux make extensive use of the Gnu operating system sources (utilities, tools, etc.) and thus have many command-line commands in common. However, they are alike only at the source-code level -- their running programs (executables) are not at all cross-compatible.
Uh, no. MacOS and OS X is actually UNIX not Linux. Linux is a clean-room work alike constructed copy of UNIX.
Apple macOS and OS X are the world's best selling, completely certified POSIX® compliant and TradeMarked by the Open Group versions of UNIX being sold today. UNIX preceded Linux by at least two decades.
For a good explanation of the history of the two, read this link.