Is LinkedIn created mainly for the IT people?

Hey people. I have many complaints from my LinkedIn friends in terms of their failure for landing a job position. They have great professional accounts with recommendations but they don't land any related job, no one is interested in their applications!

On the other hand, if you just one programming related term in your account (like data mining), you immediately appear in many job searches. My account is not related to programming, but I just added the expression "data management" and…

Is LinkedIn created mainly for the IT people?