At Orbee, another word for a source is a vendor.
A Source is where the user came from to get to your site.
They could be search engines, website name (for referrals), and (direct). Search Engines include Google, Bing, Yahoo, etc. If a website links your car dealership's website from their website, then their website name will show up as the source (Direct) sources are users who come directly to your website by typing the URL into the address bar at the top of their internet browser