Secondary storage

Secondary storage

1. OPTICAL

   • is the storage of data on an optically readable medium
   • Recorded by making marks in a pattern that can be read back with the aid of light, usually a beam of laser light precisely focused on a spinning optical disc
   • Advantages
     • Large storage capacity is available
     • Very cheap
     • Can sometimes be re- used
   • Disadvanatges
     • Some older computers do not read the disks
     • Sometimes not reusable

2. SOLID STATE

   • all-electronic device that is an alternative to a hard disk, solid state drives are faster than hard disks.
   • It uses a type of memory called "flash memory" which is similar to RAM. it remains even when it loses power. also uses a grid of electrical cells to quickly send and recieve data
   • Advantages
     • Speed is delivered u to 100 times the performance
     • There is lifetime cost and its really cheap and have expected to have a longer lifespan making the cost savings add up in the long run.
     • Power consumption is takes less power
   • Disadvantages
     • Upfront cost
     • Gradual wear
     • Maximum Capacity

3. MAGNETIC

   • Its a storage of data on a magnetized medium
   • It uses different patterns of magnetisation in a magnetisable material to store data. later the information is accessed using one or more read/write heads.
   • Advantages
     • Very fast access data
     • Data can be read directly from any part of the hard disc
     • Some of the magnetic storage devices are very cheap
   • Disadvantages
     • Data can be altered by magnetic fields,dust,mechnical problems
     • Gradually lose their charge over time-data lost
     • Regular crashes can damage the surface of the disk, leading to loss of data in that sector