Google Analytics Traffic Sources/Medium Tips

There are much confusion about the definitions of terms used in Google Analytics regarding traffic sources/medium. Here’s some tips:

(direct) / (none)
The visitor hasn’t been referred from another website and either used a bookmark or typed the website directly into the browser.  It should be categorized as just a visitor who did not visit from a link or search engine.

google.com / referral
google.ca / referral
google.uk / referral
Not all referrals from Google.com domains come through organic search or AdWords ad listings. Referrals may come from a variety of sources, including Google Groups posts, base.Google.com listings, Google map, or static pages on related Google sites. Such visits are tagged as [referral] instead of [organic].

mail / referral
Visitors visited your site from / with email programs

IP address / referral
Visitors visited your site from their own IP address, for example, when a person subscribes to the feed of a blog, and when the person uses third party software to receive the feeds, and presses on the feed, he is using his IP address to view your entry.