12、Software engineering is the application of a systematic, disciplined, quantifiable approach to the development, operation, and maintenance of software.it encompasses techniques and procedures, often regulated by a software process, with the purpose of improving the reliability and maintainability of software systems.The effort is necessarily by the potential complexity of those systems, which may contain millions of lines of code.
The term software engineering was popularized by F.L.Bauer during the NATO Software Engineering Conference in 1968.The discipline of software engineering includes knowledge.tools, and method in software requirements, software design, software construction, software testing, and software maintenance tasks.Software engineering is related to the disciplines of computer science, computer engineering, management, mathematics, project management, quality management, software ergonomics, and systems engineering.