Software engineering

From Wikipedia, the free encyclopedia

Software engineering is the application of a systematic, disciplined, quantifiable approach to the development, operation, and maintenance of software.[1] The term software engineering was popularized during the 1968 NATO Software Engineering Conference (held in Garmisch, Germany) by its chairman F.L. Bauer, and has been in widespread use since. The discipline of software engineering encompasses knowledge, tools, and methods for defining software requirements, and performing software design, software construction, software testing, and software maintenance tasks.[2] Software engineering also draws on knowledge from fields such as computer engineering, computer science, management, mathematics, project management, quality management, software ergonomics, and systems engineering.[2]

As of 2004, the U. S. Bureau of Labor Statistics counts 760,840 software engineers holding jobs in the U.S.; for comparison, in the U.S. there are some 1.4 million practitioners employed in all other engineering disciplines combined.[3] There are estimated to be about 1.5 million practitioners in the E.U., Asia, and elsewhere[citation needed]. SE pioneers include Barry Boehm, Fred Brooks, C. A. R. Hoare, and David Parnas.

Contents

[edit] Nature

David Parnas has said that software engineering is, in fact, a form .[4].[5] Steve McConnell has said that it is not, but that it should be.[6] Donald Knuth has said that programming is an art.[7]

The U.S. Bureau of Labor Statistics classifies computer software engineers as a subcategory of "computer specialists", along with occupations such as computer scientist, programmer, and network administrator.[8] The BLS classifies all other engineering disciplines, including computer hardware engineers, as "engineers".[9]

The U.K. has seen the alignment of the Information Technology Professional and the Engineering Professionals.[10] Software engineering in Canada has seen some contests in the courts over the use of the title "Software Engineer"[11]

[edit] Definition

Typical formal definitions of software engineering are

  • "the application of a systematic, disciplined, quantifiable approach to the development, operation, and maintenance of software".[1]
  • "an engineering discipline that is concerned with all aspects of software production"[12]
  • "the establishment and use of sound engineering principles in order to economically obtain software that is reliable and works efficiently on real machines"[13]

[edit] Other meanings

As Dijkstra pointed out, the terms software engineering and software engineer have, at times, also been used (or misused) in a much wider sense, particularly in America.[14] The term has been used less formally:

  • as the informal contemporary term for the broad range of activities that was formerly called programming and systems analysis;[15]
  • as the broad term for all aspects of the practice of computer programming, as opposed to the theory of computer programming, which is called computer science;[16]
  • as the term embodying the advocacy of a specific approach to computer programming, one that urges that it be treated as an engineering discipline rather than an art or a craft, and advocates the codification of recommended practices in the form of software engineering methodologies.[17]

[edit] Purpose

Software is often found in products and situations where very high reliability is expected, even under demanding conditions, such as monitoring and controlling nuclear power plants, or keeping a modern airliner aloft[18] Such applications contain millions of lines of code, making them comparable in complexity to the most complex modern machines. For example, a modern airliner has several million physical parts[19] (and the space shuttle about ten million parts[20]), while the software for such an airliner can run to 4 million lines of code.[21] See also List of software engineering topics (thematic) and List of software engineering topics (alphabetical).

[edit] Technologies and practices

Software engineers advocate many different technologies and practices, with much disagreement. This debate has gone on for 60 years and may continue forever. Software engineers use a wide variety of technologies and practices. Practitioners use a wide variety of technologies: compilers, code repositories, text editors. They also use a wide variety of practices to carry out and coordinate their efforts: pair programming, code reviews and daily stand up meetings.

In spite of the enormous economic growth and productivity gains enabled by software, persistent complaints about the quality of software remain.[citation needed]

See also: Debates within software engineering and Criticism of software engineering

[edit] The software engineering profession

[edit] Debate over who is a software engineer

The use of "software engineer" as a corporate job title dates from at least 1990[citation needed]. The person who has the job title "software engineer" and performs their job according to the job description for a "software engineer" is generally thought of as a software engineer. However, Bachelor's degrees in Software Engineering have become available from many well known universities. People who are from outside the corporate setting may believe that there are currently no widely accepted criteria for distinguishing someone who is a software engineer from someone who is not a software engineer. In addition, the industry is in the midst of a complex debate on the licensing of practicing software engineers. The two sides of the debate consider whether the job is a creative art or a repeatable science. In actual practice, the existing system of checking the work of the 'software engineer' when required by law by a state licensed professional engineer is considered adequate for legal liability reasons.

[edit] Debate over the term 'engineering'

Some people believe that software development is a more appropriate term than software engineering for the process of creating software. Pete McBreen, (author of "Software Craftsmanship: The New Imperative" (ISBN 0-201-73386-2)), argues that the term Software Engineering implies levels of rigor and proven processes that are not appropriate for all types of software development. He argues strongly for 'craftsmanship' as a more appropriate metaphor because that term brings into sharper focus the skills of the developer as the key to success instead of the "manufacturing" process. Using a more traditional comparison, just as not everyone who works in construction is a civil engineer, not everyone who can write code is a software engineer.

Some people dispute the notion that the field is mature enough to warrant the title "engineering"[citation needed]. Opposition also comes from the traditional engineering disciplines, whose practitioners usually object to the use of the title "engineer" by anyone who has not gone through an accredited program of engineering education[citation needed]. In each of the last few decades, at least one radical new approach has entered the mainstream of software development (e.g. Structured Programming, Object Orientation, ... ), implying that the field is still changing too rapidly to be considered an engineering discipline. Other people would argue that the supposedly radical new approaches are actually evolutionary rather than revolutionary, the mere introduction of new tools rather than fundamental changes[citation needed].

[edit] Education

People from many different educational backgrounds make important contributions to SE. Today, software engineers earn software engineering, computer engineering or computer science degrees.

Software degrees
About half of all practitioners today have computer science degrees. A small, but growing, number of practitioners have software engineering degrees. In 1996, Rochester Institute of Technology established the first BSSE degree program in the United States but was beaten to ABET accreditation by Milwaukee School of Engineering. Both programs received ABET accreditation in 2003. Since then, software engineering undergraduate degrees have been established at many universities. A standard international curriculum for undergraduate software engineering degrees was recently defined by the CCSE. As of 2004, in the U.S., about 50 universities offer software engineering degrees, which teach both computer science and engineering principles and practices. The first graduate software engineering degree (MSSE) was established at Seattle University in 1979. Since then graduate software engineering degrees have been made available from many more universities.
Domain degrees
Some practitioners have degrees in application domains, bringing important domain knowledge and experience to projects. In MIS, some practitioners have business degrees. In embedded systems, some practitioners have electrical or computer engineering degrees, because embedded software often requires a detailed understanding of hardware. In medical software, some practitioners have medical informatics, general medical, or biology degrees.
Other degrees
Some practitioners have mathematics, science, engineering, or other technical degrees. Some have philosophy (logic in particular) or other non-technical degrees. And, some have no degrees. Note that Barry Boehm earned degrees in mathematics and Edsger Dijkstra earned degrees in physics.

[edit] Employment

See also: software engineering demographics

Most software engineers work as employees or contractors. Software engineers work with businesses, government agencies (civilian or military), and non-profit organizations. Some software engineers work for themselves as freelancers. Some organizations have specialists to perform each of the tasks in the software development process. Other organizations required software engineers to do many or all of them. In large projects, people may specialize in only one role. In small projects, people may fill several or all roles at the same time. Specializations include: in industry (analysts, architects, developers, testers, technical support, managers) and in academia (educators, researchers).

There is considerable debate over the future employment prospects for Software Engineers and other IT Professionals. For example, an online futures market called the Future of IT Jobs in America attempts to answer whether there will be more IT jobs, including software engineers, in 2012 than there were in 2002.

[edit] Certification

Certification of software engineers is a contentious issue. Some see it as a tool to improve professional practice.

Most successful certification programs in the software industry are oriented toward specific technologies, and are managed by the vendors of these technologies. These certification programs are tailored to the institutions that would employ people who use these technologies. General certification of software practitioners has struggled. The ACM had a professional certification program in the early 1980s, which was discontinued due to lack of interest. Today, the IEEE is certifying software professionals, but only about 500 people have passed the exam by March 2005. In Canada the Canadian Information Processing Society has developed a legally recognized professional certification called Information Systems Professional (ISP).[22]

[edit] Impact of globalization

Many students in the developed world have avoided degrees related to software engineering because of the fear of offshore outsourcing (importing software products or services from other countries) and of being displaced by foreign visa workers [3]. Although government statistics do not currently show a threat to software engineering itself; a related career, computer programming does appear to have been affected [4][5]. Often one is expected to start out as a computer programmer before being promoted to software engineer. Thus, the career path to software engineering may be rough, especially during recessions.

Some career counselors suggest a student also focus on "people skills" and business skills rather than purely technical skills because such "soft skills" are allegedly more difficult to offshore [6]. It is the quasi-management aspects of software engineering that appear to be what has kept it from being impacted by globalization. [7]

[edit] Comparing related fields

Many fields are closely related to software engineering; here are some key similarities and distinctions. Comparing SE with other fields helps explain what SE is and helps define what SE might or should become. There is considerable debate over which fields SE most resembles (or should most resemble). These complex and inexact comparisons explain why some see software engineering as its own field.

[edit] History

Software engineering has a long evolving history. Both the tools that are used and the applications that are written have evolved over time. It seems likely that software engineering will continue evolving for many decades to come.

[edit] 60 year time line

[edit] Current trends in software engineering

Software engineering is a young discipline, and is still developing. The directions in which software engineering is developing include:

Aspects
Aspects help programmers deal with -ilities by providing tools to add or remove boilerplate code from many areas in the source code. Aspects describe how all objects or functions should behave in particular circumstances. For example, aspects can add debugging, logging, or locking control into all objects of particular types. Researchers are currently working to understand how to use aspects to design general-purpose code. Related concepts include generative programming and templates.
Agile
Agile software development guides software development projects that evolve rapidly with changing expectations and competitive markets. Proponents of this method believe that heavy, document-driven processes (like TickIT, CMM and ISO 9000) are fading in importance[citation needed]. Some people believe that companies and agencies export many of the jobs that can be guided by heavy-weight processes[citation needed]. Related concepts include Extreme Programming and Lean software development.
Experimental
Experimental software engineering is a branch of software engineering interested in devising experiments on software, in collecting data from the experiments, and in devising laws and theories from this data. Proponents of this method advocate that the nature of software is such that we can advance the knowledge on software through experiments only[citation needed].
Software Product Lines
Software Product Lines is a systematic way to produce families of software systems, instead of creating a succession of completely individual products. This method emphasizes extensive, systematic, formal code reuse, to try to industrialize the software development process.

The Future of Software Engineering conference (FOSE), held at ICSE 2000, documented the state of the art of SE in 2000 and listed many problems to be solved over the next decade. The Feyerabend project attempts to discover the future of software engineering by seeking and publishing innovative ideas.

[edit] Software engineering today

In 2006, Money Magazine and Salary.com rated software engineering as the best job in America in terms of growth, pay, stress levels, flexibility in hours and working environment, creativity, and how easy it is to enter and advance in the field.[23]

See also software engineering economics.

[edit] Conferences, organizations and publications

[edit] Conferences

Several academic conferences devoted to software engineering are held every year. There are also many other academic conferences every year devoted to special topics within SE, such as programming languages, requirements, testing, and so on.

ICSE
The biggest and oldest conference devoted to software engineering is the International Conference on Software Engineering. This conference meets every year to discuss improvements in research, education, and practice.
COMPSAC
The Annual International Computer Software and Applications Conference was first held in Chicago in 1977 and is designated as the IEEE Computer Society signature conference on software technology and applications.
ESEC
The European Software Engineering Conference.
FSE
The Foundations of Software Engineering conference is held every year, alternating between Europe and North America. It emphasizes theoretical and foundational issues.
CUSEC
Conferences dedicated to inform undergraduate students like the annual Canadian University Software Engineering Conference are also very promising for the future generation. It is completely organized by undergraduate students and lets different Canadian universities interested in Software Engineering host the conference each year. Past guests include Kent Beck, Joel Spolsky, Philippe Kruchten, Hal Helms, Craig Larman, David Parnas as well as university professors and students.
SEPG
The annual Software Engineering Process Group conference, sponsored by the Carnegie Mellon Software Engineering Institute (SEI), is a conference and exhibit showcase for systems and software engineering professionals. The four-day event emphasizes systematic improvement of people, processes, and technology.
INFORMATICS-INFORMATIQUE
The annual Canadian information technology, data processing and software engineering symposium, sponsored by the Canadian Information Processing Society. First held in 1958.
ICALEPS
International Conference on Accelerator and Large Experimental Physics Control Systems Conference [8]. Biennial conference covering software engineering for large scale scientific control systems. First held in 1987.
APSEC
Asia Pacific Software Engineering Conference [9].
UYMS
National Software Engineering Symposium (in Turkish: Ulusal Yazilim Muhendisligi Sempozyumu) [10] (not available in English). Biennial symposium first held in İzmir, Turkey in 2003.

[edit] Organizations

[edit] Publications

[edit] See also

Main lists: List of basic software engineering topics and List of software engineering topics

[edit] References

  1. ^ a b “IEEE Standard Glossary of Software Engineering Terminology,” IEEE std 610.12-1990, 1990.
  2. ^ a b Guide to the Software Engineering Body of Knowledge (February 6, 2004). Retrieved on 2007-02-13.
  3. ^ Bureau of Labor Statistics, U.S. Department of Labor, USDL 05-2145: Occupational Employment and Wages, November 2004, Table 1.
  4. ^ Parnas, David L. (1998). "Software Engineering Programmes are not Computer Science Programmes". Annals of Software Engineering 6: 19–37. , p. 19: "Rather than treat software engineering as a subfield of computer science, I treat it as an element of the set, {Civil Engineering, Mechanical Engineering, Chemical Engineering, Electrical Engineering,....}."
  5. ^ Parnas, David L. (1998). "Software Engineering Programmes are not Computer Science Programmes". Annals of Software Engineering 6: 19–37. , p. 20: "This paper argues that the introduction of accredited professional programmes in software engineering, programmes that are modelled on programmes in traditional engineering disciplines will help to increase both the quality and quantity of graduates who are well prepared, by their education, to develop trustworthy software products."
  6. ^ McConnell, Steve (August 2003). Professional Software Development: Shorter Schedules, Better Projects, Superior Products, Enhanced Careers. Boston, MA: Addison-Wesley. ISBN 0-321-19367-9. , p. 39: "In my opinion, the answer to that question is clear: Professional software development should be engineering. Is it? No. But should it be? Unquestionably, yes. "
  7. ^ Knuth, Donald (1974). "Computer Programming as an Art". Communications of the ACM 17 (12): 667-673.  Transcript of the 1974 Turing Award lecture.
  8. ^ U.S Department of Labor and Statistics The 2000 Standard Occupational Classification (SOC) System: 15-0000 Computer and Mathematical Occupations
  9. ^ U.S Department of Labor and Statistics The 2000 Standard Occupational Classification (SOC) System: 17-0000 Architecture and Engineering Occupations
  10. ^ 'British Computer Society' - "BCS is licensed by the Engineering Council to award Chartered Engineer status (CEng) and Incorporated Engineer status (IEng);" [1]
  11. ^ 'Professional Engineers of Ontario' - "Quebec Engineers win court battle against Microsft"[2]
  12. ^ Sommerville, Ian [1982] (2007). "1.1.2 What is software engineering?", Software Engineering, 8th ed., Harlow, England: Pearson Education, P. 7. ISBN 0-321-31379-8. “Software engineeering is an engineering discipline that is concerned with all aspects of software production from the early stages of system specification to maintaining the system after it has gone into use. In this definition, there are two key phrases:
    1. Engineeering discipline Engineers make things work. They apply theories, methods and tools where these are appropriate [. . .] Engineers also recognise that they must work to organisational and financial constraints. [. . .]
    2. All aspects of software production Software engineering is not just concerned with the technical processes of software development but also with activities such as software project management and with the development of tools, methods and theories to support software production.”
     
  13. ^ Ubiquitously cited as a quote from F.L. Bauer at the original NATO Conference on Software Engineering, the usual citation being: (January 1969) "NATO Software Engineering Conference 1968" (pdf). edited by P. Naur and B. Randell; published January 1969 Software Engineering: Report of a conference sponsored by the NATO Science Committee, Garmisch, Germany, 7-11 Oct. 1968, Brussels: Scientific Affairs Division, NATO. 
  14. ^ Dijkstra, Edsger W; transcribed by Mario Béland (1993-12-03; transcription last revised 2004-11-23). There is still a war going on (manuscript Austin, 3 December 1993). E. W. Dijkstra Archive. The University of Texas at Austin, Department of Computer Sciences. Retrieved on 2007-02-17. “When the term was coined in 1968 by F.L. Bauer of the Technological University of Munich, I welcomed it. [. . .] I interpreted the introduction of the term “software engineering” as an apt reflection of the fact that the design of software systems was an activity par excellence for the mathematical engineer. [. . .]. As soon the term arrived in the USA, it was relieved of all its technical content. It had to be so for in its original meaning it was totally unacceptable [. . .] In the mean time, software engineering has become an almost empty term, as was nicely demonstrated by Data General who overnight promoted all its programmers to the exalted rank of “software engineer”!”
  15. ^ Akram I. Salah (2002-04-05). Engineering an Academic Program in Software Engineering. 35th Annual Midwest Instruction and Computing Symposium. Retrieved on 2006-09-13.: "For some, software engineering is just a glorified name for programming. If you are a programmer, you might put 'software engineer' on your business card—never 'programmer' though."
  16. ^ Mills, Harlan D., J. R. Newman, and C. B. Engle, Jr., "An Undergraduate Curriculum in Software Engineering," in Deimel, Lionel E. (1990). Software Engineering Education: SEI Conference 1990, Pittsburgh, Pennsylvania, USA, April 2-3,.... Springer. ISBN 0-387-97274-9. , p. 26: "As a practical matter, we regard software engineering as the necessary preparation for the practicing, software development and maintenance professional. The Computer Scientist is preparing for further theoretical studies..."
  17. ^ David Budgen, Pearl Brereton, Barbara Kitchenham, Stephen Linkman (2004-12-14). Realizing Evidence-based Software Engineering. Retrieved on 2006-10-18.: "We believe that software engineering can only advance as an engineering discipline by moving away from its current dependence upon advocacy and analysis...."
  18. ^ Pecht, Michael (1995). Product Reliability, Maintainability, and Supportability Handbook. CRC Press. ISBN 0-8493-9457-0. 
  19. ^ Boeing 747, By the Numbers "Six million: the number of parts, half of which are fasteners."
  20. ^ Grübler, Arnulf (2003). Technology and Global Change. Cambridge University Press. ISBN 0-521-54332-0.  p. 33: "A Boeing 747 [contains] roughly 3.5 million [parts]... the apogee (and nightmare) of mechanical complexity is the space shuttle, with 10 million parts."
  21. ^ Pehrson, Ronald J. (January 1996). "Software Development for the Boeing 777". CrossTalk: The Journal of Defense Software Engineering. , "The 2.5 million lines of newly developed software were approximately six times more than any previous Boeing commercial airplane development program. Including commercial-off-the-shelf (COTS) and optional software, the total size is more than 4 million lines of code."
  22. ^ Canadian Information Processing Society. I.S.P. Designation. Retrieved on 2007-03-15.
  23. ^ Kalwarski, Tara; Daphne Mosher, Janet Paskin and Donna Rosato (2006). Best Jobs in America. MONEY Magazine. CNN. Retrieved on 2006-04-20., "MONEY Magazine and Salary.com researched hundreds of jobs, considering their growth, pay, stress-levels and other factors. These careers ranked highest. 1. Software Engineer..."

[edit] Further reading

[edit] External links

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