DVD-D stands for Digital Versatile Disc for Data. It is a type of DVD that is designed mainly for storing data, such as software programs, multimedia files, documents, and backups.
Think of DVD-D as a special type of disc like the ones you use to watch movies, but instead of movies, it's used to store all different kinds of important things like pictures, videos, and even computer programs.
Just like with other DVDs, you need a DVD player or drive to use them. But unlike DVDs for movies which only work on a DVD player, DVD-D can work on both computers and DVD players.
Overall, DVD-D is just another way to store important things. It's kind of like a really big flash drive or external hard drive that you can keep safe and use whenever you need to access your data.