That depends on what parts sort of social medias you're thinking of. There isn't much walls to write on, like on Facebook, and you don't have to befriend your mother. There isn't a word restriction like Twitter and you usually don't get a lot of stalkerish followers. We do have some kind of blog-thing, though! I think. Mainly it's just people posting and you replying. Nothing more serious than that, really.
Welcome, @The_Blancs! Forums are not quite like social media, no. A forum is a much more focused venue that centres around discussions, research and workshopping regarding particular topics. WritingForums.org is, of course, focused around writing. We have areas to discuss plot, settings, characters, publishing, and genres; a workshop where one might post writing for critique; fiction and poem writing contests; and many other things. Unlike social media this isn't really a venue where one posts about their daily life, like many do on social media. Instead you can see the forum as a resource writing-related problems and questions, and a community of like-minded people. However, we do have "The Lounge", an area for discussing non-writing topics in which some more social media-like content is posted (see e.g. the Happiness thread, a picture-posting thread, and many similar things). I recommend that you take a look at our New Member Quick Start and the Forum Rules if you haven't done so already. It should give you a nice introduction to what our forum has to offer.
You must become a "member", meaning you have made twenty posts and your account is 14 days old. You also must give two critiques for every one work you post for critique. After that you can post your work over in the workshop.