Optical disc
An optical disc is a type of storage media that consists of a flat, round, portable disc made of metal, plastic, and lacquer that is written and read by a laser. Optical discs primarily store software, data, photos etc. Some types of optical discs are formatted to read only, meaning users cannot write on the media. Others are read/write, which allows the user to save on the disc.
These discs store items by using microscopic pits (indentations) and lands(flat areas) that are in the middle layer of the disc. A high powered laser light creates the pits. A low powered laser reads items from the disc by reflecting light through the bottom of the disk. The light reflected turns into bits the computer can process. A land causes the light to reflect, processed as binary digit 1. Pits absorb the light. processed as a binary digit of 0.
These discs store items by using microscopic pits (indentations) and lands(flat areas) that are in the middle layer of the disc. A high powered laser light creates the pits. A low powered laser reads items from the disc by reflecting light through the bottom of the disk. The light reflected turns into bits the computer can process. A land causes the light to reflect, processed as binary digit 1. Pits absorb the light. processed as a binary digit of 0.
Types of Optical Discs
CD-ROM - compact disc read-only memory, is a type of optical disc that a user can read but not write or erase.
CD-R - compact disc-recordable, is a multisession optical disc which users can write, but not erase data.
CD-RW - compact disc-rewritable, is an erasable multisession disc you can write on multiple times.
There are CD-ROM drives to read a CD-ROM using laser technology. CD-RW Drives read CD-RW cds and has the ability to write onto the cd using the software and drivers installed. The process of writing onto these disks is called 'burning'. Some OS, such as Windows, includes the capability of burning discs.
CD-R - compact disc-recordable, is a multisession optical disc which users can write, but not erase data.
CD-RW - compact disc-rewritable, is an erasable multisession disc you can write on multiple times.
There are CD-ROM drives to read a CD-ROM using laser technology. CD-RW Drives read CD-RW cds and has the ability to write onto the cd using the software and drivers installed. The process of writing onto these disks is called 'burning'. Some OS, such as Windows, includes the capability of burning discs.
Archive Discs and DVDs/Blu-ray
Several users use archive discs to preserve their data. An archive disc stores photos from an online photo center in the .jpg file format. People also like to use picture cds, a single session CD-ROM that stores digital versions of film using .jpg file format. Most optical discs can read an archive disc or picture cd.
DVDs store data, instructions and information in a slightly different manner. The DVD stores the pits closer together making the disc denser. It uses two layers of pits which doubles the capacity of the disc. A DVD-ROM is a high capacity optical disc on which users can read but not write or erase. The DVD-ROM drive is needed to read or play the DVD-ROMs.
DVDs store data, instructions and information in a slightly different manner. The DVD stores the pits closer together making the disc denser. It uses two layers of pits which doubles the capacity of the disc. A DVD-ROM is a high capacity optical disc on which users can read but not write or erase. The DVD-ROM drive is needed to read or play the DVD-ROMs.
Microfilm and Microfiche
Microfilm and Microfiche store microscopic images of documents on roll or a sheet of film. Microfilm is a 100-215 foot roll of film. Microfiche is a small sheet of film usually 4x6 in. A computer output microfile recorder, records images onto the film. However the images are so small they must be read by a microfile or microfiche reader.
Enterprise
Large corporations uses servers on the network to provide storage for connected users. In an enterprise, storage systems can provide more than 185 TB of storage capacity. Enterprises use several servers and connected networks to manage and store data and information for their supporting users.