This can all be looked up in the Oracle documentation.
http://download-west.oracle.com/docs...a96625/toc.htm

But I think that misses the point. If you go for a job, your resume/CV should indicate your level of experience. If I was interviewing someone with no Oracle experience, I wouldn't be asking them about how to identify performance issues.

While DBMS_PROFILER doesn't get used as much as it should (for some reason the package is not installed by default until 10G), I would expect anyone who has worked in Oracle for a year or more to be at least AWARE of tkprof.

If your resume/CV indicates that you have experience that you don't actually have, then you are trying to lie to your prospective employer. If you have straight from college/university/training courses and that is what the employer is expecting and looking for, then being honest about what you have learnt should not be a problem.