Authoring is commonly done in software on computers with optical disc recorders. It is part of optical disc recording technologies for digital recording to optical disc. It is typically removable, rewritable and much smaller than an optical disc. ISO 9660 is a file system for optical disc media. This is a list of optical disc authoring software. The lacquer protecting the edge of an optical disc can usually be seen without magnification. GoldStar also produced some models of computer monitors and optical disc drives. An ISO image is a disk image of an optical disc. Computer case manufacturers also began to stop including -inch bays for installing optical disc drives. DiscoVision's license activities covered LaserDisc, CD, DVD and other optical disc products. The producers had tied up with optical disc maker Moser Baer for the release. RLL codes have found almost universal application in optical disc recording practice since 1980. This form of optical disc was a very early form of the DVD (). Optical disc storage is "non-volatile". Lastly, DOS allocates letters for optical disc drives, RAM disks, and other hardware.