Rufus is a useful utility, that helps format and create bootable USB flash drives, such as USB keys/pendrives, memory sticks, etc. It can be especially useful for cases where you need to create USB installation media from bootable ISOs (Windows, Linux, UEFI, etc.), to work on a system that doesn't have an OS installed, to flash a BIOS or other firmware from DOS or when you need to run a low-level utility.
Non exhaustive list of ISOs Rufus is known to work with:
Arch Linux, Archbang, BartPE/pebuilder, CentOS, Damn Small Linux, Debian, Fedora, FreeDOS, FreeNAS, Gentoo, GParted, gNewSense, Hiren's Boot CD, LiveXP, Knoppix, KolibriOS, Kubuntu, Linux Mint, NT Password Registry Editor, Parted Magic, Partition Wizard, Raspbian, ReactOS, Red Hat, rEFInd, Slackware, Super Grub2 Disk, Tails, Trinity Rescue Kit, Ubuntu, Ultimate Boot CD, Windows XP (SP2+), Windows Vista, Windows Server 2008, Windows 7,Windows 8, Windows 8.1, Windows Server 2012, Windows 10, Windows Server 2016