1 Canker sores are small, painful ulcers on the inside of the mouth, tongue, lips, or throat.  Symptoms of canker sores include small, painful, crater-like ulcers.
Facebook is the biggest social network on the web, both in terms of name recognition and total number of users. With nearly 1.8 billion active users, Facebook is a great medium for connecting people from all over the world with your business. And the site is not only the biggest network, but it's also arguably the most versatile one.
Tumblr and Twitter are two of the biggest social networks where NSFW content tends to flourish freely if you look around hard enough for it, but nothing really compares to Reddit and its very NSFW subreddit. As of February 2016, there are over 610,000 users who are subscribed to it.