On a standard keyboard the " symbol (Shift+') is most often called a quotation mark. This is also a double prime used to denote inches and seconds (also see prime). In typography, these straight double quotation marks are often referred to as dumb quotes when used as quotation marks.
In properly typeset material the dumb quotes are converted to curly quotes or typographer's quotes. When converted to curly quotes there are two separate characters used: Left Double Quotation Mark (open) “ and Right Double Quotation Mark (closed) ”. They slant or curl (in opposite directions) while the regular quotation mark or double prime is generally straight up and down.
On a Mac, use Option+[ and Shift+Option+[ for the left and right double quotation marks. For Windows, use ALT 0147 and ALT 0148 for the left and right double quotation marks (curly quotes).
