The graphic acquisition channels can be found under Analysis > Content Performance > Content Reach
The designation of the channels comes from Google Analytics:
Direct: A user directly types in your website URL or clicks on a link from an email, PDF, or saved bookmark. Any traffic that Google doesn’t have the source information on is also considered direct. This is why secure-to-unsecure traffic is classified as direct.
Display: A user clicks on a paid advertisement, such as a banner ad, that leads back to your site.
Email: You send out an email campaign to your customers and they click on a link in the email.
Organic Search: A user comes to your site directly from a search engine such as Google, Yahoo, or Bing. If you pay to advertise on search engines, those visitors will count as Paid Search instead.
Paid Search: A user clicks on a paid advertisement in a search engine (most commonly via Google AdWords) that leads back to your site.
Referral: A user clicks a link to your site from a page on another website.
Social: A user clicks on a link to your site from any major social channel, such as Facebook, Twitter, LinkedIn, or Instagram.