All our computers use only open source software. We have the facilities to demonstrate, advise, and install a completely free and open source solution.
Open source software for computers, be it desktops or laptops, has been around for some time now, and there is an amazing amount of choice out there to suite almost anyone. Due to the nature of open source this is not really advertised, and a lot of people don't realise there are free alternatives when it comes to choosing computer software.
You have probably heard of at least one of the main two commercial operating systems in use today; Windows and MacOS. These are of course closed source and expensive to run and maintain. The main open source alternatives are Linux (and BSD) based, they are totally free and come in hundreds of flavours. Ubuntu is probably the most well known flavour of Linux today, and in recent years it has become so easy to use that it is becoming popular with even novice computer users.
Unfortunately the corporations are trying to get their fingers in the Ubuntu pie, and integrating the system into paid for services and Amazon recommendations. This is totally against the linux philosophy, and many people are unhappy about this, causing several Ubuntu based spin off flavours to be created. Mint Linux is one quite popular version, but I find it a bit slow. Xubuntu is another that I use myself and install and maintain for friends, family and clients. It is great for general purpose computing, and I would recommend it for nearly anyone, unless you have very specific computing needs.
Closed source applications that you might be used to like Microsoft Office or iTunes will not (easily) work on an open source operating system, however there are free open source alternatives available....
Unlike closed source applications, that will usually only work on closed source operating systems they have been designed for, open source applications are usually designed to work on all operating systems. This means you dont have to be using Linux to take advantage of open source applications.
Firefox (web browser)
LibreOffice (word processor and spreadsheet)
Gimp (photo editing)
and many more high quality open source apps will run on Windows, Mac and Linux.