FREE Coursera(must have verified student email)

[Merlin]

To be honest, I don't trust such courses.

There is no reason not to trust them.

In most cases, Coursera courses are regular college courses, taught by college instructors, but with minor alterations to support distance-learning students. Since they are not for credit, they may use volunteer student aids and include peer review as part of the evaluation process. But you can still learn quite a bit if you take it seriously, and that is really why you take the courses. Of course, if you pay, you can also earn a certificate that is useful on your resume and LinkedIn profile, but to me, education is the key reason I am interested in Coursera.