The term “organic traffic” is used for referring to the visitors that land on your website as a result of unpaid (“organic”) search results. Organic traffic is the opposite of paid traffic, which defines the visits generated by paid ads. Visitors who are considered organic find your website after using a search engine like Google or Bing, so they are not “referred” by any other website.
A good example is Facebook Custom Audiences. Within this Facebook supports email targeting, the ability to upload customer email addresses and then target those users on Facebook with tailored ads. This lets you micro-segment based on your existing customer database. One application is customer loyalty marketing, promoting offers to existing high value users via Facebook ads.
PPC (paid search marketing): PPC (pay per click) advertising involves paying to have search engines display your website offer in or alongside search results. For example, Google's Adwords program will display your ad at the top or right side of the search results page (placement depends on many factors including keywords and quality of ad). Google will also feed your ads to websites running its Adsense program. There are other types of PPC marketing, such as Facebook Ads. In PPC advertising, you pay each time someone clicks on your offer. Paid search differs from organize search in that you're paying to have your website or offer displayed higher in search results.
Guest blogging purely for inbound links is a flawed strategy because the value of those links are going down. However, guest blogging for traffic is still an incredibly viable strategy. While that inbound link you get at the end of a guest post doesn’t have as much SEO value as it used to, it still has the value of exposing your content to a new audience.