Linux brought the use of Live CD’s, and the OS installation being small in size, some of the Linux Distributions got popular, then It was the ability to install Linux OS from USB or run Linux from Bootable USB Drives instead of live CD’s.
A simple tool called UNetbootin, can make installation/Bootable liveUSB drive of various Linux/BSD distributions to a partition or USB drive.It can create a dual-boot install, or replace the existing OS entirely.

UNetbootin has built-in support for numerous distributions, including Ubuntu, Fedora, openSUSE, PCLinuxOS, Linux Mint, ArchLinux, Debian, CentOS, Frugalware, FreeBSD, NetBSD,and many more.

Here how you can create a LiveUSB of any Linux Distribution Using Unetbootin.

1. Format the USB Drive using a FAT32 file system, in some cases you might need to format it as a FAT16 file system.
   [ Note : USB Drive should atleast be 1-2GB,based on the linux distribution]
2. Run the application, to open the GUI of the tool
   
3. Select the OS you want from the download list or point it to your ISO if you already have it.
4. Select your USB stick.
5. Load the OS onto your USB stick.
6. Reboot your system and make sure to select USB from the boot devices menu.

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