請問如何區分【GDP (PPP)】& 【GDP (nominal)】有什麼不同處：

員外的算盤

請問如何區分
【GDP (PPP)國內生產總值（購買力平價）】& 【GDP (nominal)國內生產總值（國際匯率）】
有什麼不同處：

例如：Singapore
http://en.wikipedia.org/wiki/Singapore

GDP (PPP)		2011 estimate
-	Total	$314.911 billion[6] (38th)
-	Per capita	$59,711[6] (3rd)
GDP (nominal)		2011 estimate
-	Total	$259.849 billion[6] (38th)
-	Per capita	$49,270[6] (13th)

例如：Malaysia
http://en.wikipedia.org/wiki/Malaysia#cite_note-imf2-8

GDP (PPP)		2012 estimate
-	Total	$472.942 billion[8]
-	Per capita	$16,186[8]
GDP (nominal)		2012 estimate
-	Total	$278.680 billion[8]
-	Per capita	$10,466[8]