projects saved them time and money, because they didn’t have to write everything themselves. And because the quality of the existing code was technically excellent, they improved their product very quickly.
LECTURER: OK. So, what’s your second point, Jack?
JACK: I was coming to that! My second point is that Netscape wanted to provide the opportunity for developers outside their company to contribute code to the product.
LEILA: Yes, but there’s no evidence that that would happen. If anything, programmers from Netscape were more likely to be involved in other open source projects.
MAJED: Well, I don’t agree with that, Leila, because from what I’ve read, lots of people contribute to open source development programs.
EVIE: Sorry, but who are we talking about, exactly? People with good programming skills working in their bedrooms, or people employed by large software companies who work on these projects as part of their employment?
LEILA: Yes, we need to be clear here. It must be a mixture of both. Anyway, I’d just like to say that according to what I’ve read, open source products are becoming increasingly important for commercial companies.
EVIE: In what way?
Leila: Well, if you make your basic product open source, you can then provide a premium version which customers pay for. Also, you can charge users for support services which they may want to use if they don’t have good in-house technical support.
EVIE: I don’t get that. How can you charge for something if you are giving it away?
LEILA: What I’m trying to say is, some users may be happy with a basic product which they get for free. Others may want a more advanced product or they may need to buy in expertise for this particular software.
MAJED: I still don’t understand. Can you give me an example, Leila?
LEILA: OK. Look at it this way. Companies which use a proprietary operating system for their servers, for example Windows, have to pay a fee for the software. If they use an open source operating system, such as Linux, they can get it for free. But their technical support may not be trained in using Linux, so they may need to buy in technical help while they are learning. So on the one hand, they may have to pay for support, but on the other,
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they get the operating system free. And support is a lot cheaper than the system software.
MAJED: So the software developers make money by saving their customers money?
LECTURER: Absolutely. But it’s not just about cost. In making a decision on which type of software to use, companies have to think about other issues such as security, how quickly the software becomes obsolete and how easy it is to modify it to their own needs.
MAJED: Yes, and I’d just like to say something else. As I mentioned before, lots of people help to write open source programs because they want to help other people. Open source can do a lot of good things for society in general too.
Unit 9, Lesson 2, Exercise B≤2.5
Part 1 Good morning, everyone. I’m going to talk to you this morning about human–computer interaction, usually referred to as HCI. The purpose of HCI as a field of study is to optimize the performance of humans and computers together as a system. In particular, I’m going to talk about the two different components of HCI – namely, the human sciences and the computer sciences. I’m going to talk first about the human sciences, and I will outline some of the issues in psychology relevant to HCI. After I’ve described these, I will go on and do the same for the computing science components. I will also give you a summary of how they link together.
But before we begin I have a little story to tell
you … I once spent six months working on a project, designing an interface for a new manufacturing system. It used state-of-the-art technology and made good use of colour graphics to show the operator what was happening with each of the machines on the production line. Sadly, when we came to rolling it out, we hit a major problem. On the factory floor, the operator had to wear protective clothing, with a special face mask which turned everything to black and white. He wanted to be able to use the interface without taking off the mask, which meant that he couldn’t see the colour. Consequently, a lot of my six months’ work was wasted. The point of the story is that it is really very important to consider all the human aspects when designing a user interface – in this case, the work environment. So … to get back to the main part of my lecture ...
Now, it’s pretty clear that in order to be successful, system designers need to pay attention
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