If you hold the mouse over someone's avatar, you'll notice that a summary of their bio pops up.
When I hover my mouse over your name, it pops up a box with your name, age, location, and the first few lines of your bio. It should work the same for you when you hover over people's names.
It means people like Agnostic.com.
What do you mean by "hover"? Dictionary.com definition:
Hover
verb
to hang fluttering or suspended in the air: The helicopter hovered over the building.
to keep lingering about; wait near at hand.
to remain in an uncertain or irresolute state; waver: to hover between life and death.