Job seekers need it for finding advertisements (obviously!); for finding sites to monitor for opportunities; to obtain information about industries, trends, labour markets, companies, important people and so on; and for thinking about career alternatives.
Career developers might be able to develop some of the great teaching examples presented in this course too.
A pleasant way to learn google, complete with exercises. If you're impatient then take the advice of one of the people that comments in the lifehacker article and use the googleguide.
I hope that the graphic presented here can be considered so-called 'fair use'. It consists of crops from two screen captures from the first video in the course.