LinkedIn is primarily a professional networking site. Your public profile appears in Google and other search engine results. Your full profile is viewable to signed in LinkedIn members.
Using LinkedIn you can connect with and follow individuals and organizations whose status updates will then appear in your LinkedIn Newsfeed. Individuals you connect with will also see your updates in their feeds.
You can create a comprehensive profile similar to a resume, including links to your publications.
Most people just use the free service, but premium (fee) options are also available.
This is a lengthy video but in it you will learn a lot about setting up your profile and effecitvely using LinkedIn's many features.