This post was originally published on go2linux.org, a Linux blog I ran from 2007 to 2011. The domain is no longer mine, but I am the original author. I am republishing it here on garron.me with corrections and improvements.
mkfs.vfat is used to format a file system using the FAT32 file system.
Usually needed to format thumb usb disks.
In Arch Linux you need to install, dosfstools
sudo pacman -S dosfstools
This will get you mkfs.vfat and mkfs.msdos
If you need to format using ntfs install
sudo pacman -S ntfsprogs