What's this dot?

Hi, I’m fairly new to Blender and am having problems trying to “reset” the centre of an object. As can be seen in the shot below I must have LMB at some point and moved the cursor. Now I can’t rotate the square from it’s centre. I tried setting the Pivot point to Bounding Box Center but it has made no difference. I’m having trouble understanding how this works with cursor location and object rotation. I’d be most grateful if any one can shed some light on this for me please. Thank you.http://www.redbackonline.com/blender/rotate.jpg

Just go into the editing buttons window (F9) and select “Centre new” (under the bit that says “Mesh”).

Thank you animatinator. So much to learn… so little time… Thank you. It seems so blindlingly obvious once somebody shows you. :slight_smile: