A standard single-sided, single-layer DVD holds up to 4.7 gigabytes of data. There are three other DVD formats that each have greater data capacity than 4.7 gigabytes.
A double-sided, single-layer DVD doubles the capacity to 9.4 gigabytes. Double-layer DVDs also exist, but are not compatible with DVD-RW drives. A single-sided double-layer DVD holds 8.5 gigabytes, while a double-sided one again doubles that to 17 gigabytes. The previous generation of data storage, the compact disk, or CD, has a storage capacity of only about 700 megabytes, while the next generation, the Blu-ray, has a capacity of 25 gigabytes for a single-sided, single-layer disk.