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Monday, January 13, 2020

Hardware and software Requirements Essay

Floppy disk: The standard 3 1/2†³ floppy disk is a thin, flexible plastic disk coated in metal oxide, enclosed in a rigid plastic casing for protection. A standard high density disk has a storage space of 1. 44 Megabytes.   Hard Disks: The hard disk used with conventional PCs consists of one or more disk platters, which are permanently sealed inside a casing. Hard disks have a capacity of between 2Gb and 10Gb, though external hard drives can be plugged into the computer to provide extra storage space. For large-scale applications storing huge amounts of data, more hard disks would be used. The disks can be fixed or removable, although the fixed disks are more reliable and have more storage capacity. Data is stored on the concentric tracks, which are divided into sectors. Data is then stored in one of the sectors so that it minimises the movement of the read-write heads, thereby minimising access time.   CD-ROM: CD-ROMs can store around 680Mb of data, which is the equivalent of hundreds of floppy disks. CD-ROMs do not transfer data as quickly as the hard disk drive. As the name suggests the disks are read-only memory. Unlike a magnetic disk they are created by burning tiny holes into the surface of the disk, a laser beam is then reflected off the surface of the disk, detecting the presence or absence of pits, which represent the binary digits. Worm disks (Write Once, Read Many): These look very similar to the CD-ROM in appearance but are gold rather than silver in colour. These disks can be used to write your own material and are ideal for archiving or storing images or data, which will not be changed. They are popular in the pirate industry because a i 5 blank disk can store upto i 20 000 worth of software and sell for i50 – i 80. They are used by less reputable PC company’s which install the software onto the PC so they can charge the consumer more for the package. However because of the competition in the pirate industry at present many of these carry viruses which can cause chaos on the hard drive.   Magneto-optical disks: Magneto-optical disks integrate optical and laser technology to enable read and write storage. A 5 1/2†³ disk can store up to 1 Gb. These disks may in future replace current magnetic disks, but at present the technology is still developing and the disks are too expensive, slow and unreliable to be in widespread use. Magnetic tape: Magnetic tape was developed in the 1950s and very quickly became the primary means of storing data. The data is stored on magnetic tape in the form of dots of magnetism. It is used widely for archiving past transactions or other data that may be needed again, for example, old news readings that have been collected over a number of years.   Jaz Drive: Two Gigabytes is a tape drive and a mass storage device mainly used for backing up large files or batches of files i. e. end of day transaction backup for banks or businesses. Software requirements and techniques Software is the name given to the programs that direct the operation of the computer. It can be divided into two main groups, system software and applications software. System software is the programs required to run the computer system and applications software is the programs required to carry out a particular application such as stock control Systems software This is the software that the microcomputer system needs to run. In this group there are three divisions: operating systems, utilities and compilers/interpreters/assemblers. Operating systems: An operating system is a set of programs that allows the user to perform tasks without having to know how they are done. For example, a user can give a command to save a file on disk without having to know where the file will be stored or how it will be retrieved again. Applications programs are usually written to work with a particular operating system e. g. Excel will only work with Windows and not with Apple Mac, which has a different operating system. Utility programs: Utility programs perform common tasks that every computer user will need at one stage or another. They carry out such jobs as formatting and copying disks, deleting files from disks, sorting information into a required order, and to help with the testing of programs that have been written. Compilers, interpreters and assemblers: These are programs that translate the programming language that is used into a form that the computer can understand. Compilers work by translating the whole of the program from what is known as the source program into the object program which will be in a form that the computer can understand. Interpreters are programs that translate and execute source programs one statement at a time. An assembler is a program supplied by the computer manufacturer that will translate a program that was written in assembly language (low-level programming language) into machine code. Applications software: In large organisations that have a mainframe or minicomputer we would find that programmers were employed whose job it would be to write the programs for the applications that the organisation wished to have run on the computer, such as payroll, stock control or hospital appointments. The software may be designed specifically for one particular company and written especially for them using a programming language or software such as database management system. Alternatively, the software may be purchased ‘off the shelf’. General purpose software: Most general purpose software is sold as a package, including a CD containing the software. Below is the most common packages that you would find on the market to date: 1. Applications: spreadsheets, database, word processing, Desk Top Publishing 2. Presentation: CD based presentations (Power Point, Director) 3. Internet Publishing: web page development software (Front Page, Dreamweaver, Flash) 4. Programming Software: BASIC, Visual Basic, C++, Java, Pascal, HTML 5. Creation and Editing: Photo Shop, Paint Shop Pro, Premier, Coral Draw 6. Utility: Anti-virus, tidy and compression, Doctors. The newer computer systems will have these utilities on them already. Software such as word processing, spreadsheet and databases is sometimes refereed to as generic software. This means that many of the packages can be made to do many different tasks, and is not specifically for one type of application. The other types of application software such as stock control and payroll as mentioned before are special purpose because they have been designed to complete one particular task. Conclusion: I found this assignment very interesting and now feel I have a much sounder understanding off computer hardware and software. I would have liked to incorporate more images into the assignment as reference to each of the products described, but was unable to find all of the images that I required, and also had problems trying to transfer them from the internet. Apart from this I feel quite satisfied with the overall assignment and hope that I have entered all the data needed and presented it in a clear fashion. Bibliography Corbitt T, (1990), Information Technology And Its Applications. Avon, United Kingdom: Bath Press Heathcott P M, (2000), ‘A’ Level Computing. Ipswich, United Kingdom: Payne-Gallway Publishers Ltd References Corbitt T, (1990), Information Technology And Its Applications. Avon, United Kingdom: Bath Press Heathcott P M, (2000), ‘A’ Level Computing. Ipswich, United Kingdom: Payne-Gallway Publishers Ltd.

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