CDs and DVDs both are used for digital data storage, but a DVD is always used for larger files such as videos. There are a few ways to store data on CDs and DVDs, blank copies of which can be purchased at electronics stores.
The disc with the least amount of storage space is the CD-R, which can hold 700 MB, or approximately 80 minutes of audio.
A CD-RW has the same storage capacity as a CD-R, but data can be removed and replaced, unlike the CD-R which can only be burned once.
DVDs can hold significantly more data than CDs. DVD-Rs hold approximately 4.7 GB of data. And unlike CD-Rs, DVD-Rs can burn videos that can be watched directly on any DVD playing device.
A DVD-RW has the same storage capacity as a DVD-R, but its benefit is that it can be recorded multiple times. These discs are the best choice for people who use DVD video recorders with their TVs.
Double layer discs available for blank CDs and DVDs offer twice the usual storage capacities.