1. Computer hardware is any
physical device associated
with a computer system.

2. A computer system consists of a few basic
components:
CPU Main Memory
Buses
Input Auxiliary Output
Device storage Device

3. Zooming in on the components:
Input Any hardware device
Device that sends data to the
computer.
Allows the user to
interact with the
computer.

4. Zooming in on the components:
Input Any hardware device
Device that sends data to the
computer.
Allows the user to
interact with the
computer.
Examples are:
keyboard and mouse.

5. Zooming in on the components:
Output Any hardware device
Device that outputs data from
the computer.
Allows the user to see
the results processed by
the computer.

6. Zooming in on the components:
Output Any hardware device
Device that outputs data from
the computer.
Allows the user to see
the results processed by
the computer.
Examples are:
monitor and printer.

7. Zooming in on the components:
CPU Central processing unit or
microprocessor.
The 'heart' of the computer.
Processes the input data,
prepares the result
acordingly and produces
the output.

8. Zooming in on the components:
CPU Central processing unit or
microprocessor.
The 'heart' of the computer.
Processes the input data,
prepares the result
acordingly and produces
the output.

9. Zooming in on the components:
Main Stores data that is needed by
Memory the CPU for execution - loses
all data when the power is
switched off.
Primary memory - directly
accessible by the CPU.

10. Zooming in on the components:
Main Stores data that is needed by
Memory the CPU for execution - loses
all data when the power is
switched off.
Primary memory - directly
accessible by the CPU.
Examples are:
Random access memory
(RAM), Read-only
memory (ROM).

11. Zooming in on the components:
Auxiliary Stores information over a
storage longer period - preserves
data after the power is
switched off.
Secondary memory -
not directly
accessible by the CPU.

12. Zooming in on the components:
Auxiliary Stores information over a
storage longer period - preserves
data after the power is
switched off.
Secondary memory -
not directly
accessible by the CPU.
Examples are:
harddisk (internal) and
usb stick (external).

13. Zooming in on the components:
Buses System within the computer
hardware that moves data
between the components.
There are several types of
buses. The type is
determined according to the
specific components it
connects.
Interconnection
system.

14. Zooming in on the components:
Buses System within the computer
hardware that moves data
between the components.
There are several types of
buses. The type is
determined according to the
specific components it
connects.
Interconnection
system.

15. Zooming in on the CPU...

16. CPU
ALU Cache
Memory
Control Registers
Unit
Interprets the instructions loaded into the main
memory. The instructions either come from the
input device or a software program stored in the
auxiliary memory. Generates signals to the other
components (tells the other components what to
do and when).

17. CPU
ALU Cache
Memory
Control Registers
Unit
Arithmetic Logic Unit. Responsible for
the arithmetical and logical operations
(the actual work the computer does). A
computer can have more than one ALU.

18. CPU
ALU Cache
Memory
Control Registers
Unit
Smaller and faster memory inside the
CPU. Contains a copy of frequently used
instructions and data from the main
memory. Reduces the average time to
access memory.

19. CPU
ALU Cache
Memory
Control Registers
Unit
Memory within the CPU for temporarily
storage of information during
processing, such as instructions supplied
to the control unit and results of
operations performed by the ALU.

20. Why is there memory everywhere?
The storage of data and instructions is
devided between different components as
there is a tradeoff between: the speed at
which the CPU can access the stored
information, storage size and cost.