secondary storage essay
SECONDARY SAFE-KEEPING Secondary storage space provides cheap, nonvolatile high capacity storage. There Are quite simply two types of secondary safe-keeping: * Permanent magnet devices 5. Optical products MAGNETIC GADGETS Magnetic Disc The Magnetic Disk is definitely Flat, rounded platter with metallic layer that is rotated and balanced beneath read/write heads. It is just a direct access gadget, read/write head can be moved to any location on the plate. Magnetic hard disk drives provide storage area for considerable amounts of data and instructions which can be rapidly accessed. For info recording, the top of a disk is broken into a number of hidden concentric circles called tracks.
The tracks are figures consecutively from outmost to innermost beginning from zero. The amount of tracks varies between hard disks, from as little as 40 about some small , low ability disks to several thousand upon large, substantial capacity hard disks. Each monitor is further more subdivided in sectors. With this, in addition to the concentric circles, the disc surface area is also split up into invisible pie-shapes segments. Therefore if there are eight this kind of pie shaped segments, every track could possibly get divided into ten parts, and of these eight portions of a track is called a sector.
Storage capacity is determined by ¢ Range of recording areas ¢ Amounts of tracks every surface ¢ Number of sectors per trail ¢ Quantity of byes per sector Magnet Tape A magnetically lined strip of plastic which data may be encoded is referred to as a permanent magnetic tape. Tapes for pcs are similar to tapes used to shop music. Keeping data in tapes is definitely considerably cheaper than storing data on hard disks. Tapes also provide large storage area capacities, starting from a few hundred kilobytes to many gigabytes. Being able to access data on tapes, nevertheless , is much sluggish than accessing data upon disks.
Tapes are sequential-access media, meaning that to get to a specific point on the tape, the tape must go through all of the preceding points. In contrast, hard disk drives are random-access media as a disk travel can get any point at random with out passing through intervening points. Mainly because tapes are so slow, they are really generally used only for permanent storage and backup. Info to be employed regularly is practically always maintained a disk. Tapes are also used for transporting large amounts of data. Tapes come in a variety of sizes and formats. Floppies A soft magnet disks known as floppy.
Contrary to most hard drives, floppy hard disks (often referred to as floppies or perhaps diskettes) will be portable, as you can remove them from a hard disk drive drive. Disk drives for floppy disks are called floppy drives. Floppy disks happen to be slower to get into than hard drives and have significantly less storage capacity, but are much less high-priced. And most notably, they are portable. Floppies are available in three fundamental sizes: 2. 8-inch: The first floppy disk design and style, invented by IBM in the late 1960s and used in the first 1970s because first a read-only structure and then as a read-write formatting. The typical desktop/laptop computer would not use the 8-inch floppy hard disk drive. 5? -inch: The common size for PCs made before 1987 plus the predecessor for the 8-inch floppy disk. This kind of floppy is mostly capable of storing among 100K and 1 . 2MB (megabytes) of information. The most common sizes are 360K and 1 . 2MB. 2. 3? -inch: The most common sizes for PCs are 720K (double-density) and 1 . 44MB (high-density). Macintoshes support hard disks of 400K, 800K, and 1 . 2MB. OPTICAL PRODUCTS Optical storage area devices shop bit principles as variants in light representation. They have bigger area thickness & for a longer time data life than permanent magnet storage.
They are also standardized and relatively inexpensive. All their uses are: read-only storage with low performance requirements, applications with high capability requirements & where transportability in a standardised format should be used. Another advantage of optical safe-keeping is that the channel itself is less susceptible to contaminants or deterioration. Optical hard drives are also fewer fragile, plus the disks themselves may easily be filled and eliminated. In addition , optical disks may store far more information, when playing a routine basis and also when combined into storage area systems. All their Types: CD-ROM (read only) * DVD (Digital Video Disk) 2. Blu-ray dvd Compact disk read-only memory (CD-ROM) It is lightweight disk having data storage capacity between 650-700 MB. It may hold wide range of information including music, full-motion videos, and text etc . It contains digital information that may be read, but cannot be rewritten. Separate pushes exist intended for reading and writing Cd albums. Since it is a very reliable storage media, it is quite often used as being a medium pertaining to distributing large amount of information to large number of users. The truth is today almost all of the software is distributed through Compact disks.
Compact disk, rewritable (CD-RW) provides rewritability for the recordable compact disc market, which will previously had offered only write-once CD-ROM technology. DVD AND BLU-RAY Digital Flexible Disk (DVD) is similar to a CD yet has much larger storage capacity and enormous clarity. Dependant on the disk type it can shop several Gb of data (as opposed to around 650MB of any CD). Dvd videos are mainly used to store music or movies and is played back on your television set or the computer system too. They can be not rewritable media. 5. Over 4 GB storage (varies with format) DVD- ROM (read only) * A large number of recordable platforms (e. g., DVD-R, DVD-RW,.. ) * Are more very compact than a CD. 2. Special laser beam is needed to read them. Blueray Technology The name comes from the blue-violet laser accustomed to read and write info. It was manufactured by the Digital versatile Disc Connection with more than 180 members. Some companies with all the technology will be Dell, Volvo, LG. Your data capacity is extremely large because Blu-ray utilizes a blue laser(405 nanometers) instead of a red laser(650 nanometers) this allows data songs on the compact disk to be incredibly compact.
This enables for more than twice as small pits as over a DVD. Because of the greatly compact data Bluray can hold almost 5 times even more data when compared to a single level DVD. near to 25 GB. Just like a DVD, Blu-ray may also be recorded in Dual-Layer file format. This allows the disk to hold approximately 50 GIGABITE. The Different versions in the formats are the following: ¢ BD-ROM (read-only) to get pre-recorded content ¢ BD-R (recordable) for PC info storage ¢ BD-RW (rewritable) for LAPTOP OR COMPUTER data storage ¢ BD-RE (rewritable) for HDTV saving