1_Magnetic Storage Devices

1_Magnetic Storage Devices

1. Hard Disk Drives

   • They have magnetic disks inside called 'platters
   • The Drive is divided into; Disk; Track; Sector; Block
     • A disk is divided into; Tracks which are the rings; Sectors which are like pizza slices of a track; Blocks which are individual storage blocks inside of a sector
   • The division of the surface of the disk is done by an OS and is called 'formatting' which is done by a utility software calle a 'Disk Formatter'
   • Writes by converting the binary data into a magnetic charge on the platter, Reads by reading the magnetic charge using the Read/Write Head.
   • Retrieval of data is quite fast however the charge degrades over time as well as this mechanical issue will cause it not to work i.e. dust on the platter.
   • Uses; Servers, Personal Computers, File Sharing etc.
   • Not very cost effective per GB but is inexpensive to read data from and fast read/write times

2. Magnetic Tape

   • Magnetic tape has data written to it similarly to HDD's, the data is converted from binary to a magnetic charge and written onto the tape., tape heads read the charge on the tape
   • Useful for mass backups however read times are long as the data is stored serially and linearly and in one long reem of data so all data would need to be scoured through to find it
   • Uses; Backups at businesses, Schools, Government etc.
   • Very cost effective but the tape heads are expensive

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