What is the difference between DVD and USB?
You might see DVD and USB as two different options when buying a software program. The DVD version is distributed on a DVD, which means you'll need a DVD drive to install it. The USB version comes on a USB flash drive, which means you just need a USB port to install it.
Since many modern computers (especially laptops) don't have DVD drives, software is often distributed via digital download or on a USB flash drive. If you are presented with the options of DVD or USB when buying software, the USB version is probably the better choice since it is more likely to be compatible with future computer systems.