TRANSCRIPTS
you could use it to play games, produce assignments, watch films, listen to the radio or make phone calls. The list of things you can do with a general purpose computer is pretty extensive. This is because, unlike embedded systems, general purpose systems can be used for a whole range of things. Users can extend the range in a number of ways. They can reprogram them, upgrade them, add on new hardware, or install new software to increase the capabilities of the system.
OK, we’ve talked about types of systems that exist. Now let’s think about the functions of ICT systems.
Unit 3, Lesson 2, Exercise C≤1.12
Part 2 In the first part of this lecture, I defined ICT systems as two different types: embedded systems and general purpose systems. But they can also be defined in terms of what they do. Broadly speaking, ICT systems perform three functions. The first is information storage and management. For example, doctors often use information systems to store information about their patients. When a patient comes into the surgery, the doctor can call up their record from a database and see what problems and treatments the patient has had in the past.
The second function is control. What do control systems do? Well, an ICT control system is an electronic system which uses data to manage or regulate something; this could be a device or another system. An example of a control system is the one found in your washing machine. It’s the system that allows you to wash clothes at different temperatures or use different programs by simply pressing a button.
Finally, we have communications systems, which transmit data from one place to another using a range of communication channels including telephone lines, cables and satellite. All kinds of data can be transmitted: not simply text documents, but also pictures, sound and video files. If you have a mobile phone, the chances are that not only can you speak to your friends on it and send text messages, you can also take and send pictures and short videos, pick up e-mails and listen to the radio.
Of course, nothing is straightforward, particularly
in the world of ICT, and many ICT systems don’t slot comfortably into just one category because they perform one or more functions. Many of us
prefer to do our shopping online because it’s more convenient and also because there’s often more choice. A retail website lists information about what products are available for us to choose from. When an online order is placed, the system does a number of things. Firstly, this may be generating an instruction to prepare the products for dispatch; secondly, requesting payment from a credit card company or a bank; thirdly, sending an e-mail to the purchaser to confirm their order and, lastly, reordering new stock for the future. In this case, the system combines information management and communications.
So we have three types of function that can be carried out by ICT systems. In the next part of the lecture, we will consider the components of an ICT system.
Unit 3, Lesson 2, Exercise D≤1.13
Part 3 ICT systems are composed of hardware, software, data and users. In this section, we’re going to focus on hardware and software.
First, let’s define what we mean by hardware. The word hardware refers to the physical components of an ICT system. ICT systems have four basic hardware components and these are input devices, processors, storage devices and output devices.
Input devices are the devices used to capture data. They include keyboards, microphones, digital cameras, scanners and devices such as mice, joysticks or touch screens. Next, we have the processor. This is the part of the system that controls the computer hardware and acts on the data that is put into the system. It’s called a microprocessor or CPU – central processing unit. Storage devices are used to keep data that has been processed or will be processed at a later date. They include internal storage devices, such as RAM – random access memory – and hard drives, and external devices, such as flash drives or CDs. Finally, we have output devices such as printers or VDUs – visual display units – which are used to display or produce the results of processing.
Now let’s have a look at software. Software can
be defined as the instructions or programs that tell the hardware what to do with data. Software can be divided into two categories: systems software and applications software.
Systems software is the software that enables a system to work. It tells the system what to do and when to do it. Systems software includes operating
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