Comparing Uno with Leonardo some paragraphs state the differences. On the quoted paragraph it should say Leonardo instead of Uno. Uno has 14 Digital pins not 20.
Input and Output Each of the 20 digital i/o pins on the Uno can be used as an input or output, using pinMode(), digitalWrite(), and digitalRead() functions. They operate at 5 volts. Each pin can provide or receive a maximum of 40 mA and has an internal pull-up resistor (disconnected by default) of 20-50 kOhms. In addition, some pins have specialized functions:
This for beginners (me) don't get confused. New Leonardo looks good!