Learning along the way. Why is steemit called social media?

Sorry folks, I am not a tech savy person and thus have found steem to be exceedingly difficult to navigate. I will be able to add pictures and video content once I get a computer because apparently you can not manage steem on your phone.
Now the question is "Why is Steemit considered social media?" I ask this because from what I have seen so far, there is nothing social about it other than leaving comments on random post. I say random because there is no real search option when on a cell phone. I had to do an http search on google to find a page that I knew existed, then log back into steemit. There does not appear to be a "friends" list or smooth flow to the lay out.
Hopefully I will be able to figure it all out. Just like in the garden, there is what you know, what you thought you knew, and an endless supply of new and wounderfull things to learn and experiance.