Went to kitchen and tried to find out why iTunes>radio was taking so long to rebuff signal. Then when Safari wasn't working I went to Wi-Fi icon at top of monitor screen and then fooled around in Preferrnces>Network trying 'Advanced' and 'Assist me...' >Diagnostic and when i turned Wi-Fi back on and arrived at 'Select
Wi-Fi network it was unable to locate any network at all. "Unable to join Wi-Fi network you selected" which was non because it couldn't find any to make a list of and then I found 'Select location' set to dates back in May and June 2012, Wi-Fi would not turn 'ON'. I gave up and quit.
Wi-Fi icon at top of page (between Bluetooth icon and Volume control icon said, "Wi-Fi: No hardware installed"
At 1:04am I am not going anywhere but to bed. Will consult AppleCare in morning