Taken from the CompTIA IT Fundamentals Exam Guide book (2nd edition, published 2021). I'm not sure if they fixed this in newer versions, if at all.
When I had to learn Novell NetWare the textbook we received was just as bad and the instructor didn't have a clue either. Because internet wasn't exactly widely available for information like this then, we wrote a DOS batch file that discarded our input and miniced the output of the client for the practical exam. We all passed.
Well, GNU is a Linux based OS. Is they would write „GNU is a LINUX/GNU variant“ it would confuse more than it would teach.
From Wikipedia, the free encyclopedia
Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).
Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.
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