A great number of optical disks are being used in various fields. Optical disks currently include read-only disks such as the CD-ROM and DVD-ROM and record-once disks such as the CD-R and DVD-R. Rewritable optical disks include CD-RW, and DVD-RAM. Typical recordable optical media use a thin layer of gold as the reflective layer. Recordable optical media commonly have a transparent substrate, a dye containing recording layer is disposed on top of the substrate, a reflective layer is formed on top of the dye layer, and a protective layer is formed on top of the reflective layer. Rewritable optical disks like the DVD-RAM have very large capacity, they can store a good many moving/still images. When moving/still images are recorded on a rewritable storage media, information for search and retrieval of the images is created and recorded in a navigation information file on the storage media. The DVD-RAM disk comprises data sectors for use in recording data. Each data sector largely includes a header region and a recording region. DVD-RAM can berewritten over 100,000 times and Supports time slip recording and recording without border in/out writing. A CD-RW recorder can rewrite 700 MiB of data to a CD-RW disc roughly 1000 times. CD-RW uses phase change technology to alter the reflectivity of the disk surface. CD-RW recorders can also write CD-R discs.
