LinkedIn may not be a social network you are aware of. You might have a Facebook page or an Instagram account because you use them personally. But, LinkedIn is another social network you should use.
LinkedIn is more of a business and employee social network. You create a profile that is similar to your resume. But, LinkedIn allows you to create Company Pages. You can post updates similar to the other social networks and make connections with people. These connections are another form of networking. Finally, if you have employees, LinkedIn provides ways to post job openings.