Answer 1

https://en.wikipedia.org/wiki/Software_engineer
A software engineer is a person who applies the principles of software engineering to the design, development, maintenance, testing, and evaluation of computer software.
Prior to the mid-1970s, software practitioners generally called themselves computer scientists, computer programmers or software developers, regardless of their actual jobs. Many people prefer to call themselves software developer and programmer, because most widely agree what these terms mean, while the exact meaning of software engineer is still being debated.