Hardware and software Paper
Keyboards: The keyboard is the most common used input device, and it is used to enter commands and key in data. The keyboard is divided into four parts;
-The function keys over the top
-The letter keys in the main section
-The numeric pad on the right
-and finally the cursor movement and editing keys.
Mouse: The mouse enables you to move the arrow cursor all over the page it is much easier to use the mouse then using the keyboard, you position the arrow on the item of your choice and press.
Scanner: A scanner reads words, and pictures and then translates it into the pattern of light and dark into a digital camera and the computer stores it. The best type has to be the flat bed scanner which works in similar ways that to a photocopier. You put the page flat on the bed and then the sensor that like a photocopier, passes it translate into the computer.
Digital camera: A digital camera is similar to a normal camera but that’s only looks. The digital camera, instead of recording It, the camera converts light intensities into digital form that can be stored on a disk as a data file.
Microphones: The microphones of a computer are just the same as of normal microphones. They are used with voice recognition or simply for the Internet so you can speak to the person on the other side. It takes spoken words and translates them into digital signals.
Joystick: The joystick is used for playing games. It is used to move the (car, plane or person). Buttons on top and the side are used to perform such other moves of the (car, plane or person). They can’t be used in programs like word-processing, spreadsheet or database, but are used in CAD (computer aided design) software.
MAIN PROCESSOR UNIT:
CPU: The central processing unit or (CPU) for short or microprocessor, is the computers main component that interprets and carries out the commands that are given to it. It can fetch, decode and execute any instruction, and transfers data from one computer to another.
Memory: Memory is used to store the programs you use and is the working area that processes the current data (e.g: the letter you write or word-processing). It also comprises of ROM(read only memory) and RAM(random access memory).
Storage: The size of data or (storage) capacity of a computer is measured in bytes. One byte contains 8 bits. Bits stand for binary digits and is the smallest unit of data that can be stored. There are six types of storage;
– Bit: Smallest unit of data with value of 1 or 0.
– Byte: Equal to 8 bits-approximately equivalent to one character. The letters a, b and c are represented in binary code by 0110 0001, 0110 0010 and 0110 0011.
– Kilobyte (kb): Equal to 1,024 bytes or 2 10.
– Megabyte (Mb): Equal to 1,048,576 2 20 (equivalent to approximately 500 double spaced pages of text).
– Gigabyte (GB): Equal to 1,073,741,824 bytes or 2 30 (equivalent to approximately half-million double spaced pages of text).
– Terabyte (TB): Equal to ~1,099,000,000,000 bytes or 2 40
Motherboard: The motherboard is the main printed circuit board of the computer, which usually forms the “floor” of the system. All the other parts of the computer like the CPU and the memory, these components are linked by ‘buses’ which are etched into the motherboard.
Ports: Ports are the ‘sockets’ at the back of the main processor casing, which are used attach the peripheral devices (printer, monitor, keyboard, mouse, etc).
Modem: Modem come built in computers mostly. If you want to use the internet or if you want to e-mail the modem helps to run both. A modem, or modulator/demodulator allows two computers to communicate through telephone lines.
Network: Networks allow the sharing resources and data by users and, to access the network, each PC should be fitted with a network card.
Hard Drive: The hard drive is the storage area where all the applications software you use and documents you create are kept. It is also called the main memory of the computer.
Floppy Drive: The floppy drive is a removable storage area which enables you to save files on to a floppy disk so that you can take data files between home and work etc. They are flat and are made of a substance called mylar. They have a magnetic surface which allows the recording of your data.
Zip Drive: A zip drive is similar to a floppy drive but a zip drive works faster then a floppy drive a holds 100mb of data, that’s 70 times more faster then a floppy drive.
DVD Drive: DVD-ROM or (digital versatile disk, or disk read-only memory) is the same diameter as a CD but holds nearly 10 times the data. A DVD can hold between 4.7Gb and 15.9Gb data and, while it requires its own drive, the DVD drive can run the existing CDs. They have provided a way of watching digital-quality films or other entertainment.
Backing up: Even if you save your work in a computer drive, you should keep the back-up copy. Most organisations would agree because they have large amounts of work to store so they do this process of backing up.
VDU: VDUs display images (characters or graphics) generated by the computer’s video adapter. The image on the screen is referred to as ‘soft copy’-you will lose it when the computer is turned off. Most VDUs use a cathode ray tube (CRT) which accounts for their size.
Printers: when you need a hard copy of information on screen you will need a printer. The quality (or resolution) of the image is measured in dots per inch (or
Dpi). The more dots per inch the more detailed the output. Laser printer use lasers to produce an image on an electrical charge and this is fixed by heat.
Speakers: All computers come with speakers. The speaker will make a small beep to draw your attention e.g. when you have a error of some kind the computer will send this signal through the computer and you will see a message and a little beep to tell you what’s happened.
CABLES AND CONNECTORS:
CABLES: The different components of a computer system are connected by the cables.
CONNECTORS: Computers have connection signs to show the person where to put the wire in, e.g. if you were to look behind a tower case you can see the mouse sign to where you put in.
Software is the set of instructions that run hardware, without it the hardware won’t run. That is the difference between hardware and software.
BOOTING: When we switch on a computer, we need to wait until it ‘boots up’ before we can use it. The old saying is ‘pull yourself up by your footsteps’.
OPERATING SYSTEMS: Operating systems (OS) are the software programs that control the use of hardware resources. For example;
– Central processing unit (CPU) time.
– The allocations and use of memory
– The allocation and use of disk space.
– The operation of peripheral devices, such as printers.
APPLICATIONS SOFTWARE: Application are sometime referred to as packages or the programs that are used to run the computer.
Word processing: Word processing enables you to manipulate text-based documents – for example, you can enter text, edit and format it, change the presentation, etc.
Spreadsheet: Spreadsheets are used to enter only numerical data like numbers, it is used to process numbers in a similar way to the word processing. They are used to enter formulae’s into cells, they can also be used to make graphs.
Databases: A database can contains data but produces information from this data as a result of the processes carried out within it. Foe example the data in a library would contain the names, addresses of all the members that is a example of data.
Desktop Publishing: Purpose-written desktop publishing (DTP) software is more sophisticated than the word processing software. For example, the text for inclusion in a newsletter would be created in a word processing application, spell checked, edited and saved.
Graphics: Graphics are computer-generated images, such as pictures or illustrations. The range of graphics software is extensive and you have probably come across images stored in word processing software (e.g. Clipart) and images created on the computer using lines and shapes (e.g. circles, rectangle, or square).
Personal Organisers: Personal organisers are now useful tools in big organisations, they can be set up to offer prompts automatically to remind you of important dates and events and can also provide an easy reminder of your most used telephone numbers.
E-mail: E-mail has gone popular as now people use it even more then before. It enables people to communicate over the globe. It has been designed so that people don’t have to waste time writing a letter when they can easily send through the E-mail. E-mails are known to be legal documents, you can be prosecuted if you write something that could be construed as libellous.
Utilities: These programs provide diagnostic and measurement routines that check the performance of your computer. An e.g. of this is Anti-virus software which is a utility program that can scan any files for any virus, it can also detect a virus as well.
PROGRAMMING LANGUAGES: Computers software is written in a programming language. Some are very complex and may require experts to use them. The two e.g. of these are C++ and Java. There are those languages which are produced by the computer automatically when writing macros.
STAGES OF DEVELOPMENT: Before you can design or write a computer program, there are many stages of development that you must go through when doing this process, these are as follow;
– Analysis of the requirement – what does the computer program need to achieve?
– Design of solution.
– Development of the program – probably broken down the into small subprograms.
– Implementation and testing of the program, including training of the eventual users of the program.
– Preparation of documentation, which will include documentation relating to the actual program and documentation for the users (i.e. a users’ guide or manual).
– Ongoing maintenance and development of the program.