Software engineering is the application of engineering to the design, development, implementation, testing and maintenance of software in a systematic method.
Typical formal definitions of software engineering are:
• “Research, design, develop, and test operating systems-level software, compilers, and network distribution software for medical, industrial, military, communications, aerospace, business, scientific, and general computing applications.”
• “The systematic application of scientific and technological knowledge, methods, and experience to the design, implementation, testing, and documentation of software”.
• “The application of a systematic, disciplined, quantifiable approach to the development, operation, and maintenance of software”.