what is difference between a system engineer and a software engineer
Generally, a CS or Software Engineering degree or equivalent is required for these positions. Systems Engineer -- Works on systems in a more holistic way across multiple technologies (including software, hardware, and human processes).
Software Engineer -- Works on any task that requires the design and development of software. They are not restricted to front-end (web) technologies. The work can be in front-end (web) or back-end (server) environments, or on applications written for the desktop or for mobile devices.