Main reason of increasing popularity of Linux is because there are many Linux distributions available to choose from. 
Every Linux distribution has its own strength which attracts user to adopt that Linux distribution.
As an open source operating system Linux is always free to use. There are many Linux distributions are available and every distribution is trying to make Linux more easy to use and more powerful than any other OS.
5 Best Linux Distributions
Ubuntu
Ubuntu is most popular Linux Distribution in market. With its easy installation and user friendly interface makes it more popular to new Linux switchers. It comes with many free bundle software which fulfills almost all requirements of users. Ubuntu is a community developed operating system that is perfect for laptops, desktops and servers. Whether you use it at home, at school or at work Ubuntu contains all the applications you’ll ever need, from word processing and email applications, to web server software and programming tools.
Fedora
Fedora was introduced after Red Hat discontinued its Free Red Had distribution. Fedora is sponsored by Red Hat. By name Fedora can be the most popular Linux distributions as many knows it as Red Hat product. Fedora is easy to install and comes with lot of free applications. Linus Torvalds, the creator and primary maintainer of Linux use Fedora which inspire many to use Fedora.
Debian
Ubuntu Linux is based on Debian which tells Debian’s popularity. Debian GNU/Linux provides more than a pure OS: it comes with over 25113 packages, precompiled software bundled up in a nice format for easy installation on your machine.
openSUSE
openSUSE is quite user friendly Linux, with great user interface and Vista like start menu. openSUSE includes YaST (Yet another Setup Tool) to make installing applications very easy. It is not easy to install for new users. openSUSE project is sponsored by Novell. openSUSE focus on easy to use and improve hardware support.
Arch Linux
Arch Linux, a lightweight and flexible Linux distribution that tries to Keep It Simple. Arch Linux is for expert Linux user as it installs with bash commands no GUI desktop. You can install basic KDE desktop on Arch Linux. It is mostly used on web hosting servers for fast performance.
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