Secondary storage

• Secondary storage - is where data is stored when not in use (non-volatile)
• Examples of secondary storage - magnetic hard drive , CD , SSD
• HDD is made up of a stack of magnetised metal disks
• HDD has a large capacity , slow read and write speed , portable and reliable , longer read and write time than SDD .
• SDD has no moving parts and a lower capacity than HDD. Has the fastest read and write speed and is the most expensive.
• Optical disk drive has very slow read and write speeds , lowest capacity , is portable but not reliable.
• Optical disk drive examples include - CD’s , DVD’s and Blue-Ray Discs.
• Magnetic tape drives have low cost per gigabyte, high capacity, long term reliability and are portable. However they have slow read/write at start sinks tape is written sequentially when finding specific data