Chapter 1: Hardware - Pearson Schools

Figure 1.5 A laptop computer
A notebook computer is a small laptop computer that is about as big as an
oversized book. A notebook computer is likely to be half the size of a laptop and
is lighter and easier to carry.
A netbook computer is a very small laptop that is optimized for Internet and
email access. It is intended to be light and easy to carry and has a long battery
life. For example, the Packard Bell Dot S2 netbook has a 10.1 inch screen,
weighs 1.25kg and has a 10-hour battery life.
A hand-held computer or Personal Digital Assistant (PDA) or palmtop
can fit in one hand or in your pocket, but it is too small for general work. A
PDA usually has a touch-sensitive screen. Although PDAs can be temporarily
attached to a keyboard, you cannot comfortably type a long document into a
PDA. A smart phone is a mobile phone with the functions of a PDA. Handheld
computing devices can perform a range of activities such as personal
record-keeping and satellite navigation.
A games console is a PC that is designed specifically for playing games and is
likely to have these features:
Chapter 1: Hardware
A screen that displays graphics very quickly.
A large hard disk for saving games; gamers often have a large
number of games.
A game pad used to control the games.
Possibly an Internet connection for playing online games.
A desktop PC may have a better specification than a games console but it is
likely to be more expensive. Examples of games consoles are: Microsoft Xbox®,
Sony PlayStation® and Nintendo Wii®.
Figure 1.6 An Xbox 360 games console
An embedded computer is designed for and built into a specific application
where it will perform a limited range of dedicated functions. The size and
functionality of an embedded computer depends on the application. They may
be very small devices built into a single microchip and may control, for
example, DVD players and mobile phones.
Processors
A processor or microprocessor is built into a microchip that has memory and other
components built into it. The microchip itself is often referred to as the ‘processor’. If
there is more than one processor built into the microchip, then the microchip is
referred to as the ‘processor’ and processors built into it are referred to as cores.
The processor accepts input data, this is processed under the control of a stored
computer program, and produces the output. A computer program being
processed is loaded into the RAM. The program instructions are sent to the
processor one at a time and the processor carries out the instructions.
An important feature of a processor is the speed at which it can process
instructions. It is better to have more and faster cores, which will enable a
computer to run applications quickly; however, faster multicore processors are
expensive.
The processor speed required depends on what the computer is to be used for. An
AMD Sempron or Intel Pentium Dual Core processor might be sufficient for a
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