There are various methods of storing and retrieving both data
and ready information in computers from primary to secondary
storage systems. Data may be stored in different storage devices
in the computer. There are three basic methods used to retrieve
data from computers; Sequential Access Method This method of
data access is for example applied on reel type magnetic tapes.
The data is stored in a logical sequence. The data that was
stored first will appear first in the storage device. To find
any specific file the device starts searching from the beginning
and goes through all files till it finds the specified data. For
example in magnetic tapes the device has to rewind to the
beginning each time a file is searched and look in sequence till
it finds the specified one. The rewinding and searching makes
sequential access devices practically slower. Direct Access
Method In direct access method, the device can retrieve the
required piece of data directly without the need of any
sequence. Though data in direct ac