LinkedIn has many useful services:
It is used by recruiters and headhunters to find possible candidates when doing searches. Your LinkedIn profile shows your title, current and former employers, job responsibilities, skills and other qualifications. This is available to premium users of the site, not the ordinary rank-and-file.
2. It is useful to job hunters trying to find someone in a given company, If you are researching a company you CAN try to find someone in your network who is employed there to get information about the company, company history and culture and maybe even some information about who can be contacted as part of your job search.
3. It allows you to track companies so that you might see if an opening in a local company has opened up or who they may have recently hired.
4. It has an alumni facility to see if you can link up with people that you might have worked with. This can also be useful in a job search when you are trying to build a network
5. Another poster has mentioned the use of groups. You can belong to a professional or location group and post questions to that specific group. I belong to a group centered on my place of residence. The group has held several network sessions in the last year for both job-seekers and people looking for business contacts.
6. You can ask questions of your network. I had an interview last May in an industry that I knew nothing about. I was looking for key accounting metrics or measures used in this industry. I got about 15 responses from people in the field as well as CPA’s about common measures of performance. Helped immensely in the interview although I did not get the job.
It all depends on what you make of it and how much exploration you do of the site’s features.