cp/usth/ICT2.7/P1L1 Introduction and Overview Subtitles/2 - Importance of Software Engineering - lang_en.srt

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First, let me start by asking a couple of very

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natural questions that you might have when considering whether to take

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this course. The first one is what is software engineering.

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And the second, very related one, is why do we need

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it? So what I did was actually to go out

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and ask some of the main experts in the field, both

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in academia and industry, these very questions and let's see what

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they said. What is software engineering and why is it important?

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>> Okay, can I start with another question?

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>> Of course.

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>> Okay, first what is a computer? It's a programmable device. So the essence

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of computing is programming. So program development

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is basically the most essential use of the

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computer. So software engineering is the discipline

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that investigates program development. So, how can it

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been done more efficiently? What's the best

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way of doing program development? And how can

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you develop reliable programs? So that's how I would define

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it. But I consider any

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software development activity software engineering activity

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>> Software engineering is the systematic application of methods to build

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software in a rigorous way. And I think one of the

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aspects that I like to bring into the notion of software

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engineering is that it's something that involves not only kind of

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technically building the system but understanding the

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requirements, working with stake holders. Trying to

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find a solution that balances all of the stakeholder needs in order to deliver

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the software thats tested and its rigorous to meet the needs of a stakeholder.

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Well, software engineering is the whole process

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of creation of software using engineering principles.

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>> My view is kind of a holistic

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view and I think about it from the perspective

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of how is software engineering different from programming.

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So, I think that research about programming is all

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about the create part of software. And that

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software engineering is about the entire life cycle. So,

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that's one aspect. And the other aspect of the

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definition is it's about quality, the quality of software.

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Software engineering even considers things long after you ship which we all know

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is one of the, it is the largest economic piece of software development.

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>> So, improve, software engineering process

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for better software productivity and quality.

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>> The set of activities that one engages in when building software

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systems or software products. It's fundamentally a venue-creating

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activity. It involves social processes.

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>> Software engineering is the act

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of many people working together and putting

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together many versions of large and complex

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systems. And our world depends on software,

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software is immensely complex and we need

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many, many smart people to build these things.

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>> Well, engineering I think is the activity of envisioning and

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realizing valuable new functions with sufficient

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and justifiable confidence that the resulting

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system will have all of the critical quality attributes that are necessary

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for the system to be a success. And software engineering is the

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activity of doing this not only for

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the software components of engineering systems but

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for the system overall, given that it's

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so heavily reliant on it's underlying software technologies.

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>> So, I would say software engineering is the

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kind of art and practice of building software systems.

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>> Software engineering, in a nutshell, is a set of

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methods and principles and techniques that we have developed to enable us to

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engineer, or build, large software systems that

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outstrip or outpace one engineer's or even a small

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team of engineer's ability or abilities to understand

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and construct and maintain

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over time. So it requires a lot of people, it requires a long,

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term investment by an organization or a number of organizations, and often times

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it requires support for systems that that are intended for one purpose but end

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up getting used for many additional purposes in addition to the original one.

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>> Software engineering is about building and constructing very large-scale

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high-quality systems, so the high quality is the big issue.

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>> Software engineering is engineering discipline of developing

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software-based systems, usually embedded into larger systems composed of

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hardware and and humans [LAUGH] and business

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processes and processes in general. And why is that important?

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Well, because software is pervasive in all industry sectors

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and therefore systems must be reliable, safe and secure.

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>> Why can't we just get that by sitting down and writing software?

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>> Well, you could if software was small and

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simple enough to be developed by one or two

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people together in a room. But software development now

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is distributed, involves teams of people with different backgrounds

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who have to communicate with each other. It also involves customers,

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clients, users. Software engineers have to work with

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hardware engineers, with domain experts and therefore,

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well, no, we can't simply sit down and start coding.

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>> Software engineering is mostly being able

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to program. And you need to be able to put big

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systems together so that they actually work. That's my simple definition.

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>> And if you don't use software engineering practices,

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you're not going to be able to put them together?

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>> Well, you're not going to be able to reliably

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put them together. So basically, you could maybe hack something up,

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but it's not going to necessarily stand the test of time.

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If somebody wants to change it it's probably going to break.

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>> It's important

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because if you don't think about how you're building this system and

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how you're trading off different aspects,

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like performance and scalability and reliability, then

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it's going to end up breaking or not lasting very long or not,

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not doing everything that you want it to do, or being really expensive.

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>> If it's not done in a principled way it will

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be bad and every user will suffer. That's why we need

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software engineering.

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>> Why is it important? Because, I mean these two goal, productivity, faster,

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in developing software. And higher quality

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would be apparently important. Software is everywhere.

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>> It's important because we use software in everyday life. Everything's

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built on software systems. And these are ubiquitous across our society.

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>> It's

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important because software is everywhere around us and the way we build it,

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and the way we maintain it, is something that determines almost a basic

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quality of life nowadays. And getting that software right can make a difference,

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oftentimes, between a really fun product and one that you won't like to use

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a reasonably successful company, or one that fails. And in

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more extreme cases even the difference between life and death,

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if you think about the software that runs in the

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airplane on which many of you fly on a regular basis.

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>> There are programs out there that if they screw up we are all screwed.

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>> Software engineering is crucially

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important because it's the engineering discipline

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that is uniquely capable of carrying out

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the engineering mission for software reliant systems.

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>> In the U.S we've all seen an unfortunate example with

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a system that went badly wrong in healthcare.gov and that system wasn't

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engineered correctly. And I think if we look at the reasons for

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that, they stem back to somewhere at the intersection between requirements and

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architecture and politics and project management, and all of these things are

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important concepts that have to go into the software engineering mix.

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>> It would end up in lots and lots of chaos because people

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wouldn't know how to organize themselves and

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wouldn't know how to organize software. Many

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of software engineering has very simple rules that you need to apply properly in

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order to get things done. And people who look at these rules and think,

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these rules are so super simple. This is totally obvious. But once

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you try to apply them, you'll find out they're not obvious at all.

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>> Now that we've heard these experts, let me show you an

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example that illustrates what can happen

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when software engineering practices are not suitably

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applied. [NOISE].