Moreover, supervisors need to be in touch with their students and suggest and encourage reading material in print and allow them to ask questions which they should be able to answer rationally and to the point. Interaction with the supervisor to come up with a research topic for students is important.
That way students do not get lost as I have already mentioned that there is too much information on the web. They need to come to a compromise with their supervisor about what languages and tools to use so that they can focus on them, gain intelligence of the required technologies for their research topic and eventually soar high.