GCSE ICT exam notes Input Peripherals (devices) Keyboard, including specialised keyboard Mouse, touch pad, tracker ball (like an upside down mouse), joystick Graphics digitiser (sometimes called graphics tablet) Touch sensitive screen Light pen Scanner, digital camera for photographs or video Microphone Sensor Output Peripherals (devices) Screen (monitor or VDU) Printers (dot-matrix, laser, ink-jet) Plotters (draw graphs often linked to scientific equipment) Speakers, headphones Motors and switched output in control systems (light bulbs etc.) Storage devices and media ROM (Read only memory) and RAM (Random Access Memory) Hard and floppy disks Magnetic tape CD-ROM, CD-Recordable, CD-Rewriteable DVD ROM, DVD RAM Desk top publishing Features of desk top publishing packages can be used to enhance the presentation of a leaflet: templates tables and tabs bulleted lists use of white space upper and lower case justification titles and headings subscript and columns fonts and sizes superscript special symbols bold and italic text graphics headers and footers Word Art colour charts and graphs drawing tools borders and shading dividing lines (rules) Control software Cast your mind back to LOGO – control a robot by giving it simple commands FORWARD 50 RIGHT 90 FORWARD 50 RIGHT 90 would draw a square of size 50 FORWARD 50 RIGHT 90 FORWARD 50 Spreadsheets Spreadsheets are used to do calculations. You need to know how they work – specialised terms. Cell is the name of each box on the grid they are referenced with a letter and number (e.g. C5). You can format the data held in the cells in many ways, bold, centre, italics, underline, certain number of decimal places, currency etc. You need to be able to talk about the advantages of using a spreadsheet to do calculations over pen and paper. You can save and edit work, alter the amount entered and all relevant calculations will be recalculated and the new answer worked out without you having to do all of the sums again etc. Can draw graphs. Flowcharts You need to be able to follow and add to a simple flow chart: Sensors Know the place of sensors in systems flowcharts. Think about temperature sensors (thermostats) in central heating systems. They constantly measure the temperature and if it gets too cold they turn the heating on. If it gets too hot they turn it off/down etc. E-mail You need to be able to talk about electronic mail and the advantages / disadvantages over other more traditional methods of communication. It is a way of sending a message to somebody over the internet. You can send attachments, so you can send pictures, business reports, video clips…… you can also send it to more than one person at once. However, you cannot be sure that the person has read or received it; it is less personal than a letter or phone call. How secure is it? Purposes of operating systems The computers operating system is a program that controls the hardware directly. Operating systems perform the following tasks: They provide a way for the applications software to communicate with the hardware. For example, in Word if you click on the printer icon the operating system gives an instruction to the printer to start printing. They manage the system resources such as memory and allocate central processing unit (CPU) time to the task being run. They manage the transfer of data to and from the various peripherals (keyboards, mice, scanners, printers etc.) They manage system security. Many operating systems allocate certain rights to users. A user can only do certain things on entering a password. The operating system provides an interface between the user and the computer hardware. Without an operating system a computer would be useless. The first thing the computer looks for when it is switched on is the operating system. Some software will only run with certain operating systems e.g. Microsoft Word, Excel, Access etc. will only run with Windows 95, Windows 98, Windows XP etc. operating systems. User Interface The user interface is what you see when you turn on the computer; it consists of the cursors, prompts, icons, menus etc. which allow you to interact with the computer. Ideally the user interface should be as user friendly as possible so it is obvious to someone who has never used the software before what to do. User interfaces can be: command driven menu driven graphical (referred to as a graphical user interface (GUI)) Graphical User Interface (GUI) A graphical user interface provides a way for the user to communicate with the computer through pictures (icons) and through pull down menus. Windows is an example of a GUI. Command driven interface With a command driven interface you type in a command (usually abbreviated) in order to get something done. Command driven interfaces are not easy to use. In order to get the computer to do things you have to remember lots of commands. These commands are rarely the same in different packages so people often get them mixed up. Some people, mainly those who are used to using them, prefer them to menu driven interfaces as once you have learnt all of the commands they can be quicker to use. Menu driven interface This type of user interface produces all of the commands within a program as a list, or menu, and the user can make a selection by using either a mouse or keyboard. Microsoft Windows is a menu driven environment. Networks – WAN and LAN Networks come in two sizes – Local Area Networks (LANs) and Wide Area Networks (WANs). A LAN is something like a small company or a school, the computers are normally all in one building and communication is normally made via wires or cables. A WAN is when computers are spread over a much larger area and communication is normally made via telephone lines or satellite. A bank system may be a WAN where communication is maintained to a head office from local branches. Discuss the advantages and disadvantages of networks over stand alones Advantages Expensive peripherals such as laser printers and scanners can be shared amongst the networked computers Messages can be sent between users via an internal mail system All users can access the same files so this avoids file duplication Network software can be purchased which is usually cheaper than individual licenses. Disadvantages if a WAN is used sophisticated equipment is needed and the rental of telecommunication links is very expensive A loss in the ability to transfer data for even a short time can cause havoc, with tasks having to be performed manually File security is more important with networks. For example if a virus were to get onto the network then it could affect all of the networked terminals. Wiring can be expensive both to buy and to install. Wiring has to be sunk to avoid it trailing across a floor where it would be dangerous. System life cycle This is basically what you have done for your major project. You will need to be able to talk about what happens in the different sections. Advantages and disadvantages of the internet There is always an essay style question. Make sure you make your answers relevant to the scenario in the questions.