The system unit is the core of the computer system. It is a rectangular box placed on or underneath your desk. The box contains many electronic components that process information, the central processing units (CPU) is one of the main components. The microprocessor or the CPU acts as the brain of the computer; another part is the random access memory (RAM). It stores information that the CPU used when the computer is on. RAM information deletes as soon as the computer switched off. On the back of the system unit there are cables plug into a specific ports. Peripheral device or device (hardware) is not part of the system unit.
Mouse is use to show and select items on the computer screen. The first mouse looks a bit like a real mouse nowadays we have different shapes of mice. It is connected to the system unit by a long wire however since there are many technological improvements now we have wireless mice. The mouse usually contains a primary buttons, a wheel and a secondary buttons. The wheel allows the user to scroll through the screens for information. The pointer may change its appearance depending where it is situate on the screen. Primary button selects items on the screen by simply clicking on it. It is the principal way to interact with the computer.
The main use of the keyboard is to type text into the computer, it contains letters and numerical keys. The keyboard also has some special keys such as the function keys which is use to perform different functions relied on where they are use. Numeric keypad authorises the user to enter numbers in a quicker way. The navigation keys perform almost the same task as the mouse as it allows you to move your position within a document or webpage.
A monitor shows a see able form of the information text and graphics on the computer screen. It is like a television as it displays still and moving pictured. There are two types of monitors, the cathode ray tube (CRT) and the liquid crystal display (LCD). They are both design to make sharp images. The only differences between the two monitors are: the cathode ray tube is enabling you to afford it as it is cheaper and the liquid crystal is thinner and lighter.
Speakers are use to hear the sound effects from the computers and listen to music. It is either built in the system unit or connected to the computer using cables.
An operating system is the essential interface that is connect to a computer and performs various functions. It is software that acts like the core of computer system. The basic functions of the operating system is the drivers and the security concerns.
Drivers are programs to enable the operation of the devices specially the one installed on the system (mouse, keyboard, printer, etc). It translates the commands from operating system and also translates it back from the component to the operating system. The operating system also performs other functions such as debug errors and maintains the system.
As computer software is a human creation. It makes the operating system lie down to errors so there are security concerns. Programmers sometime make mistakes that are often implement after testing while other software developers provide more efficient one. It means that some of the operating system is more prone to errors while the other software is more secure.
Sometimes bugs in software may prohibit the system to communicate with the hardware devices. The instabilities of the software may result to crashes, which
consist of freezing and unresponsive. This result may vary depending on the operating system. It can also lead to a point where the computer in to be reboot.
The software bugs also allows unauthorised user to get to the system since its vulnerabilities enable the attackers to exploit and take complete control of the system. They can install Malware and attack other machines. So programmers provide security patches rather than updating the operating system.
Types of Operating system
Mac occupies the medium range to high end as a result Mac are popularly considered to be more expensive than other pc’s. Though Mac suffers from relatively very few hacks, security holes Mac OS x does exist, just like in any other operating system. The Mac has seen significant market share increases in recent years, something that has also increased the amount of Mac-compatible software.
MS-DOS, which is short for disk operating system, is an operating system for PCs that uses a command-line user interface. The command-line interface is difficult to learn, and the syntax and commands are not easy for the casual user to remember.
There are several other operating systems such as Linux and other windows.
2. Compare and contrast the different formats of computer systems.
Large organisations make use of mainframe computers. Mainframes are use for applications such as Bulk Data Processing and Enterprise Resource Planning. Mainframes can be use for several small servers as it has the power to host multiple operating systems.
Minicomputers also called workstations lie between mainframes and microcomputers. They used transistor and core memory technologies. The 12-bit PDP-8 minicomputer was the first successful one.
Desktop can be use in a single location it is mainly used in workplaces and households. The power consumption is less critical to that of laptops.
Laptops can be miniaturised, optimised and it is portable. Laptops are run using battery or an external battery. They have an inbuilt keyboard, touch pad (mouse) and LCD.
3.Describe the development of the processor in the last fifty years in relation to the development of Personal computers.
A computer processor is the most defining thing that man invented .It is one of the most advanced technologies available. Since the development of the computer processors is growing every year. The processors speeds are really high and still increasing. Processors are found almost everywhere cars, cameras etc. Games consoles, digital audio players and GPS device are one of the most high technologies nowadays. The development of these technologies is getting more and more complicated.
In 1972 the first processor was made by Intel, it was a 4-bit processor (Intel 4004) with a 740 kHz. After which the second processor was built 16-bit processor that had a 5 MHz speed. IBM produced a later version of the 8086 processor it was the first personal computer invented. Several technologies were being made during this time where a later version was launch the Intel 486, which has a 32-bits, and with a speed of 16MHz. The concept of multitasking was the developed where the processor was enable to run both real mode and protected mode. The System Management Mode (SMM) were attribute for power saving and computers went from Command line interface (CLI) to Windows, icons, menu and pointing device (WIMP) interaction.
In 1993 the Pentium processor (Intel) came out with a speed of 60 MHz which next after was the Pentium II which has a speed of 233MHz, Pentium III has a speed of 450 MHz followed by Pentium 4 with a speed of 1.3 GHz. Intel inaugurated the Pentium M with a lower speed of 900 MHz. It has a power saver since the battery of the laptop last longer. In 2006 Core processor was introduced which has a speed of 1.6 GHz, Core Duo has a virtualisation capability which allow the computer system to perform multitask on the same computer.
AMD even being one off the processor manufacturer it was not known until 1991 where they launched the AM386 processor with a speed of 40 MHz (same capability as the Intel 386). In 1999 Athlon Processor the crucial competitor to Pentium III was introduced by the AMD with a speed of 500 MHz. It was the first processor that
reached 1 GHz at that time. The Computer processor continues their development to get the fastest processor. From 1975 the number of transistors used on a chip has double every year.
Software programmers will create more cores that will allow multi-thread applications to be utilised. Computers will develop fast processors with multimedia applications such as graphics software, video players so on.