How do the batter and technique differ between crepes and pancakes?
Crepes do not contain baking powder or baking soda for leavening.  They also typically use melted butter vs. oil in pancakes and have a higher liquid to flour ratio.  Basic crepes contain only eggs, milk, water, a pinch of salt and flour.

You can however make them more sweet or savory by adding chopped herbs or a bit of sugar (not too much or you'll have too much browning), cocoa powder, spices such as cinnamon, nutmeg, ginger, etc.

For additional help &amp; recipe for Black Forest Cherry Crepes:  Tips for Successful Crepes