If you need a full-featured Linux system, neither of
the options above is likely to suit your requirements.
In this case, the next simplest solution is likely going
to be running a complete Linux system within your
existing system as a virtual machine.
A virtual machine requires host software that, when run,
enables your computer (Mac or Windows) to “pretend”
to be a separate (virtual) computer.
When this virtual machine is configured and running, you
can install any operating system that it supports and
access that operating system through a Mac or Windows
window just as you would any other application.
There are various forms of host software available, but
probably the best place to start is with
Virtual Box,
which is available for both Mac and Windows.
Of course, the host software only gives the virtual machine
on which to run your intended operating system. Once you
have the host software installed, you’ll also need
to install and configure your desired Linux distribution
onto that virtual machine.
Again, there are many Linux distributions from which to
choose, but a good place to start would be with
Ubuntu (stick with the
basic installation, you probably don’t need Ubuntu
Pro).
One great advantage of using this approach is that you
use your host software to install and try several
different Linux distributions side-by-side, decide which
one best suits your needs, and simply delete the unused
VMs when you decide not to use them any longer.