Linux, more precisely GNU/Linux is an operating system or a group of essential programs that makes a computer work and do something for us.It’s an alternative to Windows and MacOS and can replace them (or being booted from the same computer that has another OS.)
Generally talking,Linus is the first representative of the “free software” or better saying the software that is being distributed with a license that permits not only usage,but it permits editing,copying and analyzing.
For all the Flavors
“Linux” is used as a general term to indicate an operating system,those with specific features are called distributions.Distributions are a collection of softwares(free softwares) made to be installed and used in the simplest way from the users,giving them total power and all the necessary features to use their computer as they need.
There are tons of distributions out there,their difference is the kind of softwares they have pre-installed.Most of the Linux Distributions have a Live version,so you can try them directly by burning them on a CD or USB, without the need to install them.Try to believe.