Port is usually a wine served as a dessert wine, or as an after dinner drink. Port originated in....surprise: Portugal!
There are basically two kinds of port: Ruby Port and Tawny Port. Ruby port is a dark, dark purple and has a flavor of black cherry, chocolate, and black currant. Tawny port is like a dark maple color, and has hints of hazlenut, maple syrup, and candied orange. Ruby port is more preferrable to cook with than Tawny port, because the flavor is more versatile, being used with desserts, lamb, venison, pork, fish with a high fat content, duck, foie gras, and other game bird. Ports have an alcohol content of usually 20-22% as opposed to the 12-15% normally found in red wines.
Some popular brands of port include:
"Boldness has genius, power, and magic in it."
Johann Wolfgang Von Goethe