From b2evolution manual

The Summary sub-tab shows a table of daily totals of each type of hit on your site. If you're looking for the total number of visits of all types to your site, look in the right column. You'll also find a red X, which you can click to delete an entire day's stats data. This shouldn't be necessary since b2evolution automatically prunes this data.

While it's good to know the total number of visits you get, it's even more interesting to know how visitors found your site. b2evolution keeps track of detailed stats so you can find out.

• RSS/Atom : feed readers. These are not even identified by the User Agent but by the fact that they hit XML feed pages.
• Robots: search engines crawlers/spiders that identify themselves as such.
• Browsers: browsers such as Internet Explorer or Firefox (but also includes crawlers that pose as browsers).
• Unknown: unknown user agents.

[edit] Blacklisted

In older version of b2evolution, one summary item which does not appear separately elsewhere is the 'Blacklisted' column. This somewhat confusingly-named item does not refer to blacklisted sites but visits from your own blog to your own blog. In other words, the hits that are called 'blacklisted' are really people driving around inside your blog. So a high 'blacklisted' score shows that visitors are using many pages within your blog, as opposed to just visiting one page and then leaving.