1. ICT SHSM Certification Test – Part 2

2. Input Processing Output
Primary
Storage
Secondary
Storage
Networking
Architecture
Simple Model of a Computer –
Review

3. Primary Storage
 Primary Storage refers to a computer’s
short-term memory. This is the computer’s
RAM (Random Access Memory).
 When the user launches an application, the
most important parts of the software are
loaded into RAM for quick access.
 RAM is “volatile” – meaning that when the
computer is turned off, the contents of
RAM are erased.

4. Primary Storage
 RAM comes in a variety of sizes and
shapes, but must be compatible with the
computer’s motherboard.

5. Secondary Storage
 Secondary storage refers to a computer’s
long-term memory.
 This memory is “non-volatile”, meaning that
even if a computer is turned off, the contents
of secondary storage are preserved.
 There are three types of secondary storage:
Magnetic
Optical
Flash

6. Secondary Storage
 Magnetic memory deals with tapes or
disks coated with magnetisable particles.
 When writing to this type of memory, an
electromagnet on the read/write head is
used to align the particles in a particular
way – representing the 1s and 0s.
 When reading from this type of memory,
the demagnetised read/write head detects
the polarity of each particle to translate the
data back as 1s and 0s.

7. Secondary Storage
 Hard disk drives are examples of
magnetic storage, as are previously-used
types of memory including floppy disks
and tapes.
Floppy
Disks
Magnetic
Tape
Hard Drive

8. Secondary Storage
 Optical drives are disk drives that create
and/or play back CDs and/or DVDs.
 Optical drives use laser technology.
When a laser is shone onto the surface of
an optical disk, the amount of light
reflected back allows the computer to read
the 1s and 0s representing the data.
 In CD/DVD “burners”, a secondary laser is
used to mark the surface of a blank disk
with a pattern representing the data.

9. Secondary Storage
An internal view
of a
CD/DVD-ROM.

10. Secondary Storage
 Flash memory refers to the type of storage
used by USB “thumb drives” as well as
memory cards for cameras and portable
gaming systems.
 Flash memory is called “solid-state” memory
because it does not involve any moving
parts.
USB Flash
Drives

11. Architecture
 Architecture refers to the parts of a computer
that connect all the other parts together. This
includes:
Motherboard – all parts connect here through the
appropriate ports and slots.
Case – holds all parts in one place, has
power/reset buttons.
Power Supply – plugs into a wall socket and
provides the right voltage to each component
Fan – keeps the computer cool, prevents over-
heating

12. Architecture
Motherboard
Power Supply
Computer Case

13. Networking
 Networking hardware refers to those components
which allow a computer to communicate with other
computers.
 Networking includes using local networks (just one
machine to another) and communicating over the
internet (worldwide network of networks).
 Both types of networks require a network interface
card in each computer, along with a cabled or
wireless connection.
 Other network hardware includes the router, hub and
modem.

14. Networking
Network Interface Card Modem
Router