CD-R is short for "CD-Recordable". The discs are also known as WORM media, which stands for Write Once, Read Multiple. The advantage of CD-R over other types of optical media is that you can use the discs with a standard CD player. A related technology called CD-Rewritable (CD-RW) means that you can erase discs & reuse them, but the CD-RW media does not necessarily work in all players as technology has changed since certain models were brought out. The mechanical specifications of Verbatim media are very precise, & data written to it can be read in a wide range of drives.