The thing about SEO in 2018 is that Google changes its algorithms more than once a day! Reports say that the company changes its algorithms up to 600 times a year. While the majority of those updates consist of smaller changes, among them is the occasional, major update like Hummingbird or Panda that can really wreak havoc with your traffic and search rankings.

Organic traffic is a special kind of referral traffic, defined as visitors that arrive from search engines. This is what most marketers strive to increase. The higher you rank for certain keywords, the more often your search result appears (increasing your impressions), ultimately resulting in more visitors (aka clicks). It’s also important to note that paid search ads are not counted in this category.
PPC platforms hinge not on fixed prices, but on bids. Marketers bid for what they’re willing to pay for a single keyword click. Some industry words are much more expensive than others. The more expensive the word, the more likely you should rely on SEO to deliver traffic and leads to your organization. To find average industry CPCs, you can use Google’s keyword planner tool.

Understanding how people landed on your website is a key component of optimization. If you’ve ever looked at Google Analytics (and if you haven’t you should), you’ve probably seen the words “Direct,” “Referral,” and “Organic” in relation to your traffic. These are the sources where your users come from — or what Google calls channels. But what do these words really mean, and why do they matter?

This is the number of views that you can test each month on your website.It's up to you how you choose to use them, either by allocating all the views to one test or to multiple test, either on one page or on multiple pages. If you have selected the 10.000 tested views plan and you run an experiment on your category page which is viewed 7000 times per month, then at the end of the month 7000 is what you'll be counted as tested views quota.