Portable OS

Having an operating system like Linux on a USB drive or a CD can be helpful when you need to bring an operating system around with you. You can boot into an operating system even if the system doesn't have an OS installed. Using a USB drive is better than putting the operating system on a CD because it is faster and you can save settings and files to the drive instead of to a hard drive. A bad thing about portable OS's are that they have to be small and can't have very many extra features. Another bad thing about it is if you're using a CD, you can't bring settings or files with you.