DVD

DVD stands for Digital Versatile Disc or Digital Video Disc. It is an optical disc storage media format. It was developed and invented by Sony, and Philips in 1995. Its mainly uses as video and data storage. DVDs are of the same size as compact discs (CDs), but store more than six times of data than a CD.
DVD have a lot of types, some DVD types are DVD-ROM (read only memory) has data that can only be read and not written; DVD-R and DVD+R (recordable) can record data only once, and then work as a DVD-ROM; DVD-RW (re-writable), DVD+RW, and DVD-RAM (random access memory) can all record and erase data multiple times.