So whats all the talk about open source? Well, simply put, software that has open source code and is free to redistribute. So there is no need for pirated software. To get a proper definition read this.

There is a large number of open source applications, systems etc. There are programs, servers, programming languages, operating systems, etc. 

You can find a list of open source applications on Wikipedia.

The most common open source operating systems are Linux based. Linux is written and distributed under the GNU General Public License which means that its source code is freely-distributed and available to the general public. There are many different distributions of Linux. Currently, one of the most popular Linux distros is Ubuntu which is also my favourite and the main operating system on my computers.

You can find information about the most popular Linux distributions on Distrowatch. 

Other than Operating System you also need applications. Linux distributions come with applications for the most common tasks already installed. Many open source applications are also available for Windows and Macs.

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