DVD player Essay Example for Free

DVD player Essay Keyboard The keyboard is usually a long rectangle shaped piece of plastic with rows keys. The keyboard is used to type letters and numbers into a word processor. They are also used for gaming; some keyboards have with special gaming features. A keyboard used to be used to give commands to operate the computer before there the invention of mice. A keyboard can be connected to the computer by USB port or wirelessly. Some keyboards are designed for use by people who are visually impaired. The Waterside library has a keyboard on every computer; there are two types of keyboard in the library, the average sized plain coloured keyboards (above left) used mostly people without eyesight problems and then the larger sized keyboards (above right) for visually impaired members with a contrasting coloured keyboard. The contrasting coloured keyboard makes it easier for the visually impaired to identify buttons on the keyboard. The good thing about the larger sized keyboard is that the keys help the user to recognise when they have been pressed with a nice distinct click. The libraries facilities are available to the whole community including the visually impaired. It would be unfair for visually impaired people if they were not able to use the same facilities just because the equipment didnt suit their needs. The Library has made a big effort to make sure all sections of the community are able to use the facilities available without feeling excluded and discriminated against. If the library didnt have this specialised equipment the visually impaired members would find that they make lots of mistakes when typing and this would put them off using the library again. Mouse There are two types of mouse, they are optical or roller ball. Mice can be wired or wireless. A mouse is an object that the user holds under one of the users hands. Most mice have two buttons the left and the right. Sometimes the mouse may have a wheel between the left and right buttons. The wheel is used to scroll up and down. The mouse is used to control the motion of the cursor, which is displayed on the monitor. It can be used to open and close windows by clicking on icons and carry out tasks such as printing. All computers in the library have a normal mouse connected to them however there are two mice connected to the computers with a large keyboard, the special mouse (above right) and the Dell wired mouse (above left). The library uses wired mice because wireless mice are easily stolen as they are not attached to the computer, people can not move a wired mouse away from the computer it is wired to. The special mouse is used by people who find it difficult to use a normal mouse, for example a person who had his fingers taken off in an accident and only had a palm left would not be able to hold a mouse or click, however they would be able to use the other mouse as they could their palm to roll the ball around and press the buttons. This equipment can also be used by people with learning difficulties, poor visibility and limited hand movement. All these types of people could not have used a computer independently without assistance from members of staff, by having this special mouse means members of staff spend less time assisting one library members and are more able to help other people and organise stock. This arrangement ensures that people with disabilities are not discriminated against and are made to feel welcome in the library. Barcode scanner A barcode scanner is a laser light that scans barcodes. They save time and money. A barcode scanner can be connected to the computer through USB. They are used in shops to scan items that are purchased, issued or returned. In the library staff use a barcode scanner located at the issue desk to in libraries to scan the barcodes on stock and members cards. Before libraries used barcode scanners had to type the code in by keyboard, this took time and often mistakes were made when typing in codes, resulting in members and stock details being inaccurate. The library needs its information to be accurate as people dont want to find that stock have had taken out under there member number by mistake and that they have to pay for it because it wasnt returned. A barcode scanner is quicker and more accurate then entering in codes by a keyboard. This means that the staff can give their members a good quality service which will encourage them to use the library. Flatbed scanner A scanner scans and converts documents in to a digital image. That can be stored on the computer. It can be use by members of the library and staff. The advantage is that users can scan images/documents so as they can be sent by email or inserted in to documents. The flat bed scanners are available to staff and members in the library. They are not used very often. This is because digital cameras and phone cameras are very common and people can easily get pictures into digital format. However they are available if anyone wants to scan an A4 document. They are free of charge to use but their use is supervised by a member of the library staff. Storage devices Hard drive A hard drive is a storage device that records data. There are two types of hard drives External Hard Drives and Internal Hard Drives. The external hard disk drive is similar to internal hard disk drives; they include a normal hard disk drive which is mounted in a disk enclosure. Key benefits to using external disk drives are adding additional storage space or adding an easily removable backup source. It could also be useful for preventing the heat from the drive increasing the heat inside a computer case. The internal hard disk gives computers the ability to remember things when the power goes out. Key benefits to using internal disk drives are that it stores and retrieves data much faster than a floppy disk and CD-ROM and has a large storage capacity. It does not need connected every time the user needs to use it. In the library members are not allowed to save on to the hard drive, this is because members could be saving viruses on to the computers or filling the computers hard drive up unnecessarily. If members were allowed to save on to the hard drive all the files saved on that computer station would be available to opened, read, viewed and edit the file unless it has been saved as a password protected file. This means that any user could look at another users documents, so long as they are saved on the hard drive of the computer and there is no password. Floppy disk A floppy disk is a data storage device. Floppy disk is a plastic square shaped object with a disk of thin magnetic storage inside it. Floppy disks are read and written by a floppy disk drive. The library computers no longer have floppy disk drives on their computer. This means that members can not use floppy disks on the computers in the library. If the library computers did have a floppy disk drive and people could use floppy disks most people would still prefer to use other storage devices as they are more robust and hold a lot more data. Optical disk There are three types of optical disk they are DVD, CD and blu ray. DVDs are of the same as CDs, but they store more than six times as much data. CDs are used to store music these can be played in CD or DVD player. You cant play blu ray DVD on a normal DVD player but you can play DVDs on a Blue-ray player. Blu ray players are backward compatible; this means that blu ray player can also play normal DVDs. In the library members can not use optical drives because they are blocked instead they must use an external optical drive. The library has two external optical drives these can be borrowed from the issue desk. Members plug them in to the USB port and can then use them to open files saved on a compact disk or save on to a disk, listen to CDs and play DVDs. If a member needed to save his or her work but did not have another compatible storage device like a memory pen or have forgotten to bring it with them they can borrow the external optical drive and buy a compact disk from the issue desk and save on to that. This means that members are still able to save there documents even if they dont own another storage device or havent brought it with them. Members can request the external optical drive and use it to play music, CDs or DVDs. Memory pens Flash memory data storage device are also known Flash Drives, Memory Sticks, Pen Drives, and Memory Pens. Memory pens are more effective at transferring data than floppy disks or burning CDs. Storage capacities can range. The USB is usually protected by a removable cap. There is no external power required. Memory pens easily taken to any library and plugged in to the USB port, the documents can be opened at any computer they are plugged on to. Members of the library can use memory pens to save data on as they are unable to save on to the libraries computers hard drives. The library computers have two USB ports at the front of the computers to make it easy for the members to connect their memory pens. Random access memory RAM is the most common computer memory, it is used by programs to perform tasks while the computer is on. The data which is in the RAM will be lost when the computer power is switched off so it is important to save before switching off. Random access memory can improve performance, the more RAM in a computer the faster it will perform. There are several different types of RAM available for computers; these vary in cost and speed. The amount of RAM on the computers in the library is 512Mbyte memory . The library didnt need to buy extra RAM for their computers as the amount all ready on them was sufficient for general use and more than adequate for use in libraries where people use the computers for basic tasks such as word processing, surfing the internet and checking emails. The memory size is also adequate for the staff to run galaxy and any other software they need. By taking the standard memory the library were able to save some money which they were able to use in other areas. Magnetic tape data storage Magnetic tape is most commonly packaged in cartridges and cassettes. The device that performs actual writing or reading of data is a tape drive. When storing large amounts of data, tape can is less expensive than other data storage. Tape storage is used with large computer systems, mainly for backups and archives. However magnetic tape is much more likely to get damaged. In the library every evening when the library is closed a member of staff will put a back up tape in to the server. Staff will back up the server while the library is closed at night.