Secondary Storage
Secondary storage or secondary memory also referred as backing storage is used to supplement the capacity of main storage; the memory stores a bulk of information. It is also called auxiliary storage or mass storage. The information stored in this memory is used by the CPU by first bringing it to main memory.
Examples of Secondary Storage Devices
Some Examples of secondary storage devices are as follows:
1. Magnetic Disks
2. Magnetic Tape
3. Mass Cartridge Systems
Types of Secondary Storage
There are two types of secondary storage
Sequential Access Storage

Access through sequential access storage is non-addressable that is why an operator cannot refer directly to the contents of a particular storage location such as used with magnetic tape. This involves examining sequentially all beginning of the tape and continuing to search through all record until the desired information area is found.
Direct Access Storage

Direct Access Storage is addressable that is a given item can be selected from anywhere in storage by simply specifying the address where it is located direct access devices such as magnetic disks provide immediate access to individual records and do not require reading from the beginning of a file to find a particular record.

