Linux is a name which broadly denotes a family of free and open-source software operating system distributions built around the Linux kernel. The defining component of a Linux distribution is the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Many Linux distributions use the word "Linux" in their name. The Free Software Foundation uses the name "GNU/Linux" to refer to the operating system family, as well as specific distributions, to emphasize that most Linux distributions are not just the Linux kernel, and that they have in common not only the kernel, but also numerous utilities and libraries, a large proportion of which are from the GNU project. This has led to some controversy. 

Linux was originally developed for personal computers based on the Intel x86 architecture, but has since been ported to more platforms than any other operating system. Because of the dominance of the Linux kernel-based Android OS on smartphones, Linux has the largest installed base of all general-purpose operating systems. Linux is also the leading operating system on servers and other big iron systems such as mainframe computers, and is used on 99.6% of the TOP500 supercomputers. It is used by around 2.3% of desktop computers. The Chromebook, which runs the Linux kernel-based Chrome OS, dominates the US K–12 education market and represents nearly 20% of the sub-$300 notebook sales in the US. Linux also runs on embedded systems – devices whose operating system is typically built into the firmware and is highly tailored to the system. This includes TiVo and similar DVR devices, network routers, facility automation controls, televisions, video game consoles and smartwatches. Many smartphones and tablet computers run Android and other Linux derivatives.
When was the Linux kernel released?
By whom?
True or False: Most Linux distributions are just the kernel.
What is something many Linux distributions share?
Do they also share libraries?
Where do many of those come from?
What organization uses the GNU name?
Does the Chromebook use something from Linux?
What?
What market does it lead?
Does the Chromebook cost less than three hundred dollars?
What percentage of notebooks sold for less than three hundred are Chromebooks?
What was Linux first made for?
What structure was it based on?
Is it on phones now?
What kind?
What is an example of a big iron system?
And one more?
True or False: Linux is used by the majority of desktop computers.
What percentage uses it?
September 17, 1991
September 17, 1991
Linus Torvalds
Linus Torvalds
false
to emphasize that most Linux distributions are not just the Linux kernel, 
use of the word "Linux" in their name
use the word "Linux" in their name
yes
 but also numerous utilities and libraries,
GNU project
GNU project
TiVo
TiVo
yes
which runs the Linux kernel-based Chrome OS
Chrome OS
Chrome OS
US K–12 education
US K–12 education
yes
sub-$300
nearly 20%
nearly 20%
personal computers
 personal computers
Intel x86
Intel x86
yes
Because of the dominance of the Linux kernel-based Android OS on smartphones, L
smartphones
smartphones
mainframe computers
mainframe computers
TOP500 supercomputers.
TOP500 supercomputers.
no
2.3%
2.3%
2.3%