“Social media” is a broad term, but it has come to be fairly well understood by example now. Facebook, Twitter, LinkedIn, YouTube, Tumblr, SnapChat, InstaGram, Pinterest, Google+ … These are the most common ones at the moment. What they are from a business perspective are tools for interactive marketing. That is, you are not just posting a billboard for people to look at, but posting something that they can interact with. That interaction requires some commitment on your part as well, so be prepared before you start.
Search Engine Optimization (SEO) is just making sure that when people search for something you are promoting, they find you.
That’s different than people finding you when they search for you. You want people to search for “widgets” and find your business, for example.
The first three steps of SEO are things you can start on by yourself for free.
What happens when you find out your website has been hacked? The short answer is that someone has to clean up the mess, and make sure the hacker doesn’t just get back in the same way. The web development site Smashing Magazine has a good article that asks, “Are You Prepared Against A Hack?“, though the content of the article is really a recovery plan. Even if there are no visible signs that your site has been compromised, you’ll want to have it cleared because your search rankings will suffer. Some site visitors may see large ominous-looking warnings before they enter your site, and will report that they can’t get to it.