Computer storage holds data and information in an electromagnetic form for retrieval by a computer processor. There are two main types of storage: primary storage, which is volatile and holds data temporarily in memory like RAM; and secondary storage, which is non-volatile and holds data permanently on devices like hard disks. Secondary storage provides unlimited, portable storage as an alternative to primary storage, but is slower and cheaper than primary storage.

1. CHAPTER 2: COMPUTER
SYSTEMS
Storage

2. At the end of the lesson, student should
be able to:
 Define the meaning of storage
 State the types of storage
i) Primary storage
ii) Secondary storage

3. What is computer storage?
 Information and documents are stored in computer
storage so that it can be retrieved whenever they
are needed later on
 Computer storage is the holding of data in an
electromagnetic form for access by a computer
processor

4. Functions of Computer Storage
 Computer storage is important to help users store
programs and data to be used at a later time
 It is also useful to keep current data while being
processed by the processor until the information is
saved in a storage media
 Computer storage also stores instructions from a
computer program

5. Types of storage

6. The Differences between Primary
Storage and Secondary Storage
Primary Storage Criteria Secondary Storage
Volatile – hold data only Holding Data Non-volatile – hold data
temporarily (data lost when permanently
power is turned off)
More expensive Cost / Price Cheaper
Limited Storage Capacity Unlimited
Compulsory Need Alternative
Faster Access Time Slower
Fixed Portability Portable
RAM, ROM Type CD ROM, Floppy Disk