The Browser analysis shows the number of visits performed using the single browser versions.
Often the dimension "Device Class" is added to obtain a more meaningful analysis.
Hint: Webtrekk does not offer a dimension that shows the single browsers without their version number. However, you can create a custom metric (e.g., "Visits Firefox") which's values are filtered on a single browser (e.g., "Browser equals *firefox*) independent of its version. This metric can be used in combination with an arbitrary dimension.
Use the help in the context menu to get detailed information on the included dimensions and metrics.