A Network on LinksAlpha means a social network or content management type that you can add to your account. For example, you can add a Facebook Page as Network to your LinksAlpha account.
Once a Network has been added to your Account, you can use it for:
Network Type and total Networks
Each Network Type that LinksAlpha supports, it can result in one or more Networks getting added to your Account. For example, when you add a Facebook Profile, LinksAlpha also adds all the associated Facebook Pages, Groups, Events for that particular Facebook Profile as Networks. So, in case your Facebook Profile has 3 Pages, and is part of 4 Groups, you will end up having 8 Facebook Networks. However in case of Twitter, when you add a Twitter Profile, only 1 Network gets added 'cause Twitter Profile is the only destination you can publish content to.