The term was first used by Internet theorist John Kilroy in a 2004 article on paid search marketing. Because the distinction is important (and because the word "organic" has many metaphorical uses) the term is now in widespread use within the search engine optimization and web marketing industry. As of July 2009, "organic search" is now common currency outside the specialist web marketing industry, even used frequently by Google (throughout the Google Analytics site, for instance).
The good news is, however, indications are that dark social should decrease more and more over time, as social media as a sharing mechanism -- as opposed to email -- only continues to grow. In fact, in the same article we mentioned earlier, BuzzFeed cited a preference with millennials to share over Facebook and Twitter, alongside a longer term downward trend of sharing over email.
Another tip you can use is just reach out to the prior agency and say something like the following: “We realise you were using link networks for our website which has resulted in a Google penalty and loss in business. Can you please remove my website from any link network you have built?”. If the prior agency is decent, they will remove the links from the network.
We used to like best to see a fairly balanced mix, back when there were mostly just three sources: Organic, Direct, and Referral. Organic Search traffic is a good sign of general site health, it’s usually the top source of conversions, and it generally shows great ROI. Direct traffic is often the people who love your site or are coming back to buy after they found you in some other way. These two groups of visitors are probably the ones that bring you the most sales or leads.
Beyond organic and direct traffic, you must understand the difference between all of your traffic sources and how traffic is classified. Most web analytics platforms, like Google Analytics, utilize an algorithm and flow chart based on the referring website or parameters set within the URL that determine the source of traffic. Here is a breakdown of all sources: