Hardware & Software

Hardware & Software

1. Software

   • Software: programs that are used to control the hardware
     • Examples: Word processing package, spreadsheet package, photo editing package, web browser, CAD (computer aided design)
     • BIOS (Basic input/output system): stored in ROM and holds the boot program, used to turn the computer system on
     • OS (operating system): Program which controls the step by step running of hardware..
       • WHAT DOES THE OS DO?
         • HANDLES INPUTS AND OUTPUTS - selects and controls the operation of hardware
         • RECOGNIZES HARDWARE - the OS has to recognize any external media devices such as speakers that have been connected
         • MAXIMIZES MEMORY SPACE
         • HANDLES INTERRUPTS AND DECIDES WHAT TO DO
       • TYPES OF INTERFACE USED WITH OS
         • GUI (graphical user interface) - the usual interface in OS's such as Microsoft and Apple. They are the easiest to use as it utilizes windows, icons, menus and pointers or WIMP.
           • Windows: When the computer screen is divided into different areas.
           • Icons: small symbols or pictures used to represent files or windows.
           • Menus: Allow the user to make selections from a list. They can be pop up or pull down menus and do not clutter the desktop when not in use.
           • Pointers: Small arrows that appear when you move the mouse on your laptop/computer which is used to select items and move windows and icons
         • Command line interface: an interface where commands have to be typed in precisely to carry out actions. As a result of the difficulty to remember the commands, more people use GUIs. An example of an OS which uses a command line interface is MSDOS
         • Post WIMP: used in touchscreen devices such as PDAs and tablets. Makes use of PINCHING, ROTATING and SWIPING.

2. Hardware

   • Hardware: Tangible parts of a computer system
     • Examples: Keyboards, monitors, ROM & RAM (chips), webcams, CDs and DVDs (not the applications within), speakers, etc.
     • MAIN COMPONENTS OF A GENERAL PURPOSE COMPUTER
       • Processor and internal memory devices
         • input devices
         • Secondary storage devices
         • output devices
     • INTERNAL MEMORY
       • ROM (Read only memory): ROM is used for the storage of BIOS and the OS of a computer. ROM is also known as non volatile memory because its contents are not lost when the power is switched off. Data inside ROM cannot be edited or deleted, hence the "read only" in the name
       • RAM (Random access memory): Stores the applications which are currently being run by the user. RAM is also called volatile memory because its contents are lost every time power is lost. Data inside the RAM chip can be altered and can be written to and read from at any time.
     • CPU (Central processing unit): A.K.A processor, this chip controls the step by step running of the computer, carries out all logical calculations and operations and deals with the storage of data in memory
     • INPUT AND OUTPUT DEVICES
       • Input devices: Devices which are used to obtain raw data for the CPU to process. ex. Keyboard, mouse,
       • Output devices: Devices which relay processed information to the user for personal interpretation. ex. Monitor, speakers
     • Secondary storage devices/Backing storage: external media devices which store data processed by a computer system. Its uses include: backing up data, long term storage not always in use by the user, etc. ex. USB, external hard drive, magnetic tape, CDs, DVDs