Apple Mac: Explain Air Port icon

On the top row of my Mac’s screen, one of the icons is for Air Port. When the computer is hooked up to the Internet wirelessly through Air Port, it shows up as four dark-grey segments of circles, looking like a representation of radiating electromagnetic signals. When there’s no wireless connection to the Internet, the bars change color to light grey.

Sometimes, however, I’m at certain locations where Air Port seems to detect a wireless source. When I click on it, however, it shows neither the connected nor the non-connected icon, but instead what looks like a small rectangle, like the shape of a computer monitor screen or a television, inside a solid pie shape. I don’t get any Internet connection, but I can’t figure out what this icon is supposed to mean.

Any ideas?

Is there any resource that would show you all the icons that the system uses and what they mean?

The symbol you describe is for “Ad Hoc” ( computer to computer) networks. Avoid it.

If you’re new to Mac, the Missing Manual is a great resource, and will teach you the basics of OS X which will only change in minor ways as new updates are rolled out. (The next will be Snow Leopard, probably debuting in the fall or early next year.)