This font contains ligatures. 
In many programs ligatures are automatically turned on.

If the ligatures aren't working, please use Google to 
find out if your software supports ligatures, and
how to switch it on. 



Turn on ligatures in Word:

1. On the View menu, click Publishing Layout.
If you see a message that asks if you want 
to create a new document in Publishing Layout 
view, click Continue.

2. On the View menu, click Formatting Palette.

3. On the Formatting Palette, under Font, select 
or clear the Ligatures check box.

http://mac2.microsoft.com/help/office/12/en-us/word/item/bb7b56a7-5237-40ec-89a8-6cd103e5cd1d