• Inside a Computer

    At first glance, the small parts inside a computer may look complicated. The interior of a computer case is not particularly mysterious, though. In the following section some basic parts are introduced and explained so that anyone not familiar with computers can understand what is going on inside a computer.

    Picture 8: Inside a computer (source: Gustavb, Wikimedia)

    The motherboard is the main board of a computer. It is a thin disk containing CPU, memory, a hard disk and optical drive connectors, expansion cards for controlling video and audio, and connections to the computer's ports (e.g. USB ports). The motherboard connects directly or indirectly to any part of the computer.

    RAM (Random Access Memory) is the short-term memory of the system. Whenever a computer performs calculations, it temporarily stores the data in RAM. This short-term memory disappears when the computer is switched off. When working on a document, spreadsheet or any other type of file, it is necessary to save it in order not to lose it. When saving a file, the data is written on the hard disk, which serves as a long-term memory. RAM is measured in megabytes (MB) or gigabytes (GB). The more RAM a computer has, the more things it can do at the same time. If not enough RAM is available, the computer becomes sluggish when several programmes are open. That's why many people add extra RAM to their computers to improve performance.

    Easy-to-understand volume/size: compare byte, kilobyte, megabyte, gigabyte, terabyte
    1 Byte 1 letter or digit
    1 Kilobyte (KB) = 1000 Byte 1 page of a book
    Megabyte (MB): 1 MB = 1000 KB

    3-4 MB

    1 photo
    Gigabyte (GB): 1 GB = 125 MB = 125000 KB

    5 GB

    1 movie in DVD quality
    Terabyte (TB): 1 TB = 125 GB = 125000 MB

    7,5 TB

    Library of Congress, Washington DC, USA

    Table 1: Compare volume/size

    Software, documents and other files are stored on the hard disk. The hard disk is a long-term memory, which means that the data remains stored even if the computer is switched off or disconnected from the power supply. When a programme is run or a file is opened, the computer copies some of the data from the hard disk to RAM. When a file is saved, the data is copied back to the hard disk. The faster the hard disk, the faster a computer can start and load programmes.

    If you decide to open the computer case and take a look inside, make sure you disconnect the computer from the power supply first. Before touching the inside of the computer, touch a grounded metal object or metal part of the computer case to eliminate static. Static electricity can be transmitted through computer circuits, which can cause serious damage to the computer. You can also use an old discarded computer.

    Most computers have expansion slots on the motherboard, allowing the addition of different types of expansion cards. These are sometimes referred to as PCI (Peripheral Component Interconnect) cards. It may not be necessary to add PCI cards because most motherboards have built-in video, sound and network cards.

    A look inside a computer can be an exciting experience in ECEC centres together with the children. The children can try to give the parts names. Let the children themselves explain how they imagine a computer works and why they need the appropriate components. This stimulates the children's imagination. Afterwards, you can discuss the actual function of the individual parts in a child-friendly way. This gives the children a good idea of how a computer works. After looking inside a computer, they can be given a handout to draw the different parts.

    Comprehension Questions

    1. Can you name some hardware parts that are inside a computer?

    2. In which hardware part are software programmes installed?

    3. What does PCI stand for?