FreeDOS is a complete operating system. For new users, we recommend installing FreeDOS in a PC emulator or “virtual machine.” If you install FreeDOS directly on a computer, without using a PC emulator, you may overwrite the operating system you have now (for example, Windows.) Please be careful.
If your computer doesn't have a CDROM drive, use the USB fob drive installer. Write this to a USB fob drive and boot it to start the install. The “Full” and “Lite” versions install the same FreeDOS, but the “Lite” installer does not contain some extra bonus software packages.