A square is a large open area in a city where people walk, such as Tienanmen Square in China, Museumplein in Amsterdam or Trafalgar Square in London. Trafalgar Square: http://www.filmapia.com/sites/default/files/filmapia/pub/place/trafalgar_square.jpg Tiananmen Square: http://upload.wikimedia.org/wikipedia/commons/thumb/b/bd/Tiananmen_Square,_Beijing,_China_1988_(1).jpg/300px-Tiananmen_Square,_Beijing,_China_1988_(1).jpg Museumplein: http://thisisamystephens.com/wp-content/uploads/2012/05/i-amsterdam-letters-museumplein-edwin-van-eis_001.jpg The thing in your picture is a roundabout.

The picture is a roundabout. A square is more like a "plaza" and a junction is a series of interlinked roads. Here are pictures of all three so you can see the difference. https://www.dropbox.com/s/kl7io4sljkn5no7/Square%20vs.%20Roundabout%20vs.%20Junction.pdf

Here is a link to a project completed not far from where I live in Northern Virginia. The Gilbert's Corner Roundabouts are viewed a success in navigating the beautiful rural landscape. http://www.virginiadot.org/newsroom/northern_virginia/2009/gilberts_corner_roundabouts_complete43867.asp

I need to know the difference between a square and a roundabout. Until now I thought that a square is a circular road (which I've realised is a roundabout) And I thought a junction is where two roads(streets) cross (which seems to be only for railways). Please tell me the differences and show me pictures if possible.