As an Internet marketing strategy, SEO considers how search engines work, the computer programmed algorithms which dictate search engine behavior, what people search for, the actual search terms or keywords typed into search engines, and which search engines are preferred by their targeted audience. Optimizing a website may involve editing its content, adding content, doing HTML, and associated coding to both increase its relevance to specific keywords and to remove barriers to the indexing activities of search engines. Promoting a site to increase the number of backlinks, or inbound links, is another SEO tactic. By May 2015, mobile search had surpassed desktop search.[3] In 2015, it was reported that Google is developing and promoting mobile search as a key feature within future products. In response, many brands are beginning to take a different approach to their Internet marketing strategies.[4]

Your website should be the cornerstone of your content building strategy. Your website is the one piece of real-estate on the internet that you truly own. Facebook, Twitter, and Google are nice, but you don’t own anything on those platforms other than your intellectual property rights. The services they provide now may change in the future. Invest in the content on your website.
In 2014, BrightEdge published research that showed that 51% of channel traffic came from organic search and that it was far and away the largest channel. In the intervening years there were significant search algorithm changes that dramatically altered the layout and ranking of the search engine results pages and saw an increase in the space taken by Local, Videos, Images, Ads, and Quick Answers.
Paid social media is anything that is influenced by advertising dollars spent. Any post in your news feed that has the “Sponsored” tag is paid social media. If you then “like” that post, that is considered a paid reaction. Paid social media includes boosted posts, ads optimized for clicks, lead generation forms, video ads, among other objectives, and can be targeted by a variety of demographic and behavioral factors.
Well, yes and no. Sure, you can get hit with an algorithm change or penalty that destroys all your traffic. However, if you have good people who know what they are doing, this is not likely to happen, and if it does, it is easy (in most cases) to get your visits back. Panda and Penguin are another story, but if you get hit by those it is typically not accidental.